WO2023194840A1

WO2023194840A1 - Substituted tricyclic compounds and their use in covid-19

Info

Publication number: WO2023194840A1
Application number: PCT/IB2023/052974
Authority: WO
Inventors: Dhananjay Sathe; Dnyaneshwar Gawas; Saravanakumar IYAPPAN
Original assignee: Unichem Laboratories Limited
Priority date: 2022-04-05
Filing date: 2023-03-25
Publication date: 2023-10-12

Abstract

Present invention provides a means to prevent, cure, treat and/or to ameliorate the diseased condition in a subject caused by virus(es) from Coronaviridae family and/or a mutant thereof. The said invention further provides a means for prophylactic and/or therapeutic treatment of disease caused by virus(es) from Coronaviridae family including SARS-CoV-2 virus and/or a mutant thereof using a compound of Formula (I) or a pharmaceutically acceptable salt thereof; wherein the compound of Formula (I) is wherein Q is a group of formula Q1 or Q2; (a) (Wavy bond) represents the points of attachment; wherein R1 is -NRaRb; R2 is hydrogen or a C1-C10 alkyl group; Ra and Rb independently represent hydrogen or a C1-C10 alkyl group.

Description

SUBSTITUTED TRICYCLIC COMPOUNDS AND THEIR USE IN COVID-19

FIELD OF INVENTION

The present invention relates to compounds of Formula I and/or its pharmaceutically acceptable salts thereof for use in prevention, treatment and/or cure of disease caused by Coronaviruses.

BACKGROUND OF INVENTION

According to World Health Organization (WHO), the emergence of viral diseases represents a serious public health risk. In the past two decades, including several epidemics caused by viruses such as severe acute respiratory syndrome coronavirus (SARS-CoV) from 2002 to 2003, H1N1 influenza in 2009, Middle East respiratory syndrome coronavirus (MERS-CoV) in 2012, and the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a contagious viral illness (COVID-19) and was first reported as respiratory viral illness in Wuhan, Hubei Province, China and later rapidly disseminated across the world in a short span of time, compelling the World Health Organization (WHO) to declare it as a global pandemic on March 11, 2020. The SARS-CoV-2 pandemic has had a catastrophic effect on the world’s demographics resulting in more than 3.8 million deaths worldwide, emerging as the most consequential global health crisis since the era of the influenza pandemic of 1918 (ref: Marco Cascella et al 2022).

Coronaviruses (Coronaviridae family) are a positive-stranded RNA (+ss RNA) viruses with a crown-like appearance under an electron microscope due to the presence of spike glycoproteins on the envelope. They are the largest known RNA viruses, with genomes ranging from 25 to 32 kb and encodes four main structural proteins: spike (S), envelope (E) glycoprotein, nucleocapsid (N), The surface spike (S) glycoprotein, which resembles a crown, is located on the outer surface of the virion and undergoes cleavage into an amino (N)-terminal SI subunit (comprising of receptor-binding domain (RBD) and N-terminal domain (NTD)), which facilitates the incorporation of the virus into the host cell and a carboxyl (C)-terminal S2 subunit containing a fusion peptide, a transmembrane domain, and cytoplasmic domain is responsible for virus-cell membrane fusion. The RBD is considered to be a fundamental peptide domain in the pathogenesis of infection as it represents a binding site for the human angiotensin-converting enzyme 2 (ACE2) receptors. SARS-CoV-2 gain entry into the host cell by binding of S protein (SI) to the ACE2 receptors, wherein the host cells includes cells of the respiratory epithelium, upper esophagus, ileum, myocardial cells, proximal tubular cells of the kidney, and urothelial cells of the bladder. This binding process is followed by priming the spike protein S2 subunit by the host transmembrane serine protease 2 (TMPRSS2) that facilitates cell entry and subsequent viral replication endocytosis with the assembly of virions. These clinical and epidemiological observations provide direction on the mechanism of disease and elucidate that the virus gains entrance into its host cell via the ACE2 receptor.

Like other RNA viruses, the coronaviruses are prone to genetic evolution with development of mutations over time, resulting in mutant variants that may have different characteristics that its ancestral strain. Several variants of SARS-CoV-2 have been described during the course of current Covid- 19 pandemic among which few are considered as variants of concerns (VOCs) by the world health organization and other health agencies. Based on the recent scientific updates, few of the SARS-CoV-2variants reported include but not limited to Alpha (B.1.1.7), Beta (B.1.351), Gamma(P. l), Delta (B.1.617.2), Omicron (B.1.1.529), etc.

Coronaviruses/ SARS-CoV-2 cause mild enteric and respiratory diseases in animals and humans (Glass et al., 2004). Most human CoVs, such as hCoV-229E, OC43, NL63, and HKU1 usually cause only mild respiratory diseases ( ouchier et al., 2004). SARS-CoV-2 causes acute, highly lethal pneumonia with clinical symptoms similar to those reported for SARS-CoV and MERS-CoV-2 (Touchier et al., 2004). In contrast to SARS-CoV, SARS- CoV-2-infected patients rarely show prominent upper respiratory tract signs and symptoms. Based on current literature, most severe SARS-CoV-2 cases progressed within 14-21 days after disease onset. Interestingly, these risk factors are similar to the reported risk factors (diabetes, hypertension, obesity) associated with MERS-CoV related mortality, although MERS-CoV respiratory disease occurred in younger individuals (Assiri et al., 2013; World Health Organization, 2013).

Various therapeutic drug options available under emergency use authorization or being repurposed were evaluated in the treatment of Covid 19 including but not limited to antivirals (molnupiravir, paxlovid, remdesivir), and SARS-CoV-2 monoclonal antibodies (e.g., bamlanivimab/etesevimab, casirivimab/imdevimab), anti-inflammatory drugs (e.g., dexamethasone), immunomodulators agents (e.g., baricitinib, tocilizumab) but have attained limited success as these drug treatments providedlimited clinical utility and were based on severity of disease condition.US 10,874,687 disclosed use of purine nucleotides and their pharmaceutically acceptable salts for the treatment or prevention of CO VID - 19 caused by the SARS - CoV-2 virus. US20210283150 disclosed methods of treating feline Coronavirus infections using carbanucleoside compounds having a l'-(4-aminopyrrolo[2,l- f][l,2,4]triazin-7-yl) substituent, or a pharmaceutically acceptable salt thereof. US20210283152 disclosed methods comprising administering fostamatinib, or a pharmaceutically acceptable salt thereof to a patient having or suspected of having or expected to develop acute respiratory distress syndrome, acute kidney injury, and/or thrombosis related to COVID-19 infection.

EP3785717B1 discloses compounds for use in treating Coronaviridae virus infections, methods and nucleosides and prodrugs thereof for treating SARS virus and MERS virus.

Further, various vaccines have been designed and developed at unprecedented speed against prevention of Covid-19; and administered across the globe including the vaccine boosters. Some of the vaccines against Covid-19 include but not limited to ChAdOxl nCoV- 19 Corona Virus Vaccine (Covisheild™), inactivated virus-based COVID-19 vaccine (Covaxin™), mRNA-based vaccine (Comirnaty™, Spikevax™), etc.

Despite these efforts, the emergence of new SARS-CoV-2 variants still threatens to overturn the significant progress made so far in limiting the spread of this viral disease. Also, the cost of these available options is very high and thus provide limited access to world population for the treatment of Covid-19. Thus, there is dire need for affordable prophylactic and/or therapeutic treatment having high specificity with regards to mechanism of action for the treatment of Covidl9 or SARS-CoV-2 infection.

OBJECT OF INVENTION

An object of the present invention is to provide a means to prevent, cure, treat and/or to ameliorate the diseased condition in a subject caused by virus(es) from Coronaviridae family or a mutant thereof.

An object of the present invention is to provide a compound of Formula (I) or a pharmaceutically acceptable salt thereof, for use in prophylactic and/or therapeutic treatment of disease caused by a virus(es) from Coronaviridae family including SARS-CoV-2 virus or a mutant thereof. An object of the present invention is to provide a compound of Formula (I) or a pharmaceutically acceptable salt thereof, for use in the manufacturing of medicament for prophylactic and/or therapeutic treatment of disease caused by virus(es) from Coronaviridae family including SARS-CoV-2 virus or a mutant thereof.

An object of the present invention is to provide a means for prophylactic and/or therapeutic treatment of disease caused by virus(es) from Coronaviridae family including SARS-CoV-2 virus or a mutant thereof using a compound of Formula (I) or a pharmaceutically acceptable salt thereof.

An object of the present invention is to provide a composition comprising of a compound of Formula (I) or a pharmaceutically acceptable salt thereof, for use in prophylactic and/or therapeutic treatment of disease caused by a virus(es) from Coronaviridae family including SARS-CoV-2 virus or a mutant thereof..

An object of the present invention is to provide a means for prophylactic and/or therapeutic treatment of disease caused by virus(es) from Coronaviridae family including SARS-CoV-2 virus or a mutant thereof, by administering a compound of Formula (I) or a pharmaceutically acceptable salt thereof.

SUMMARY OF INVENTION

Present invention provides a means to prevent, cure, treat and/or to ameliorate the diseased condition in a subject caused by virus(es) from Coronaviridae family or a mutant thereof.More specifically, the said invention provides a compound of Formula (I) or a pharmaceutically acceptable salt thereof, for use in the manufacturing of medicament for prophylactic and/or therapeutic treatment of disease caused by virus(es) from Coronaviridae family including SARS-CoV-2 virus or a mutant thereof. The said invention also provides a means for prophylactic and/or therapeutic treatment of disease caused by virus(es) from Coronaviridae family including SARS-CoV-2 virus or a mutant thereof by administering to the subject a therapeutically effective amount of compound of Formula (I) or a pharmaceutically acceptable salt thereof.

Other and further aspects, features, benefits, and advantages of the present invention will be apparent from the following description of the presently preferred embodiments of the invention given for the purpose of disclosure. DESCRIPTION

Unless stated otherwise, the following terms and phrases as used herein are intended to have the following meanings:

The term, "a compound for use according to the present disclosure" or "a compound as described herein" means the compound or a pharmaceutically acceptable salt, thereof. Similarly, the phrase "a compound of Formula I" means a compound of that formula and pharmaceutically acceptable salts, thereof.

The term ‘composition’ as used herein in the present disclosure may comprise a compound of Formula I or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable excipient. The term ‘excipient’ or ‘excipients’ as used herein refers to inactive or usually inert substances that are added to the formulation which do not affect the therapeutic action of the active ingredient, but serve as a vehicle or medium for the active ingredient. It may be used to provide a desired consistency, to improve stability, and/or to adjust osmolality of the composition or adjust permeability. The excipients may be selected from the substances that are known to the skilled person for use in the form of compositions that are dependent on the route of administration. Exemplary excipients include diluents, carriers, binding agents, fillers lubricants, disintegrants, wetting agents, suitable coatings, stabilizers, sterilized water, physiological saline, suitable propellant cocoa butter, glycerides, suspending agents, emulsifying agents, preservatives polymers, solubilizers, cryoprotectants, lyoprotectants, bulking agent/s and/or pharmaceutically acceptable buffers or a mixture thereof. The selection of excipients for preparation of a composition of the present invention is well within the scope and understanding of the skilled person, and suitable excipients are listed in standard references such as Handbook of Pharmaceutical Excipients (Rowe RC, Sheskey P, Quinn M. Pharmaceutical Press; 2009); The Theory And Practice Of Industrial Pharmacy (Lachman, L., Lieberman, H. A., &Kanig, J. L. 1976). The Science and Practice of Pharmacy (Remington JP 2006) and Pharmaceutical Dosage Forms and Drug Delivery Systems (Allen L, Ansel HC 2013 Dec 23).

The terms ‘formulation’, ‘composition’, ‘medicament’, ‘pharmaceutical formulation’ and ‘pharmaceutical composition’ are used interchangeably and refer to preparations which are in such a form as to permit the biological activity of the active ingredients to be effective, and, therefore may be administered to a subject for therapeutic use, wherein the subject is a mammal, preferably human. The terms “administer,” “administering,” or “administration,” hereinare used interchangeably and refers to implanting, absorbing, ingesting, injecting, inhaling, or otherwise introducing an inventive compound, or a pharmaceutical composition thereof.

An “effective amount” or “therapeutically effective amount” of a compound or any active ingredient as described herein are used interchangeably and refers to an amount sufficient to elicit a desired biological response, i.e., treating the condition. As will be appreciated by those of ordinary skill in art, the effective amount of a compound may vary depending on such factors as the desired biological endpoint, the pharmacokinetics of the compound, the condition being treated, the mode of administration, and the age and health of the subject. An effective amount encompasses therapeutic and prophylactic treatment.

The term “treating” or “treatment” further refers to administering therapeutic agent (e.g., the composition described herein) to a subject (e.g., a human patient), who has infection caused by Coronaviridae or SARS-CoV-2 or a mutant thereof, a symptom of or a predisposition toward it, with the purpose to confer a therapeutic effect, e.g., to cure, relieve, alter, affect, ameliorate, or prevent the infection, the symptom of or the predisposition toward it. Such a subject can be identified by a health care professional based on results from any suitable diagnostic method.

The terms “SARS-CoV-2” or “Covid-19” or “Covid” or “coronavirus disease” are interchangeably used and refer to the infectious disease caused by the virus SARS-CoV-2 or a mutant thereof. The term “mutant” refers to an organism or a new genetic character arising or resulting from an instance of mutation, which is generally an alteration of the DNA sequence of the genome or chromosome of an organism. It is a characteristic that would not be observed naturally in a specimen. The term mutant is also applied to a virus with an alteration in its nucleotide sequence. Terms “mutant” or “variant” are used interchangeably herein.

The terms such as “about”, “generally”, “substantially,” and the like are to be construed as modifying a term or value such that it is not an absolute. Such terms will be defined by the circumstances and the terms that they modify as those terms are understood by those skilled in the art. This includes, at the very least, the degree of expected experimental error, technique error and instrument error for a given technique used to measure a value.

In an aspect of the present disclosure, there is provided a means to prevent, cure, treat and/or to ameliorate the diseased condition in a subject caused by virus(es) from Coronaviridae family or a mutant thereof. In an embodiment of the present disclosure, there is provided a means to prevent, cure, treat and/or to ameliorate the diseased condition in a subject caused by virus(es) from Coronaviridae family including but not limited to severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS- CoV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and/or a mutant thereof.

In an embodiment of the present disclosure, there is provided a compound of Formula (I) and/or a pharmaceutically acceptable salt thereof, for use in the manufacturing of medicament for prophylactic and/or therapeutic treatment of disease caused by virus(es) from Coronaviridae family including severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and or a mutant thereof. The medicament having compound of Formula (I) or a pharmaceutically acceptable salt thereof may be administered in a subject for ameliorating the diseased condition caused by the infection of the virus.

In an embodiment of the present disclosure, the compound of Formula I is

wherein Q is a group of formula QI or Q2;

(wavy bond) represents the points of attachment; wherein R| is -NR^aR^b;

R2 is hydrogen or a C1-C10 alkyl group; and R^a and R^b independently represent hydrogen or a C1-C10 alkyl group.

As used herein, the term "alkyl" is intended to include branched and straight-chain saturated aliphatic hydrocarbon groups and cycloalkyl group having the specified number of carbon atoms. For example, "Cmo alkyl” is intended to include Ci, C₂, C₃, C₄, C₅, C₆, C₇, C₈, C₉, and Cio alkyl groups. Preferred alkyl groups have from 1-6, especially 1-4, carbon atoms.

Example alkyl groups include, but are not limited to, methyl (Me), ethyl (Et), propyl (e.g., n- propyl and isopropyl), butyl (e.g., n-butyl, isobutyl, t-butyl), pentyl (e.g., n-pentyl, isopentyl, neopentyl). The said alkyl may be further substituted by alkyl, halogen, amides, esters, acids, cyanide, amines.

The term "cycloalkyl" refers to cyclized alkyl groups, including monocyclic ring systems. C3- 13cycloalkyl is intended to include C3, C4, C5, C6, and C7cycloalkyl groups. Preferred cycloalkyl groups have from 3-8, especially 3-6, carbon atoms. Example cycloalkyl groups include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and the like. The compounds of formula I may form salts with alkali metals such as sodium, potassium and lithium, with alkaline earth metals such as calcium and magnesium, with organic bases such as dicyclohexylamine, tributylamine, pyridine and amino acids such as arginine, lysine and the like. Such salts can be formed as known to those skilled in the art.

The compounds of formula I may form salts with a variety of organic and inorganic acids. Examples of pharmaceutically acceptable salts include, but are not limited to, mineral or organic acid salts of basic residues such as amines; alkali or organic salts of acidic residues such as carboxylic acids; and the like. The pharmaceutically acceptable salts include the conventional non-toxic salts or the quaternary ammonium salts of the parent compound formed, for example, from non-toxic inorganic or organic acids. For example, such conventional non-toxic salts include those derived from inorganic acids such as hydrochloric, hydrobromic, sulfuric, sulfamic, phosphoric, nitric, borates and the like; and the salts prepared from organic acids such as acetic, propionic, succinic, glycolic, stearic, lactic, malic, tartaric, citric, ascorbic, pamoic, maleic, hydroxymaleic, phenylacetic, glutamic, benzoic, salicyclic, sulfanilic, 2-acetoxybenzoic, fumaric, benzenesulfonic , toluenesulfonic, methanesulfonic, ethane disulfonic, oxalic, isethionic, and the like. In addition, zwitterions ("inner salts") may be formed.

The skilled person would appreciate that since the compounds of present invention have more than one basic site, they have the capacity to form a salt with more than one molecule of acid. The present invention embodies mono di or tri salts of the compounds of this disclosure. In another embodiment of the present disclosure, it is envisaged that the compound derived from Formula I includes but are not limited to one or more compounds selected from Table 1

In an embodiment of the present disclosure, it is envisaged to prepare the compound of Formula I including compounds given in Table 1. The skilled person in the art may prepare the said compound by using any of the known methods in chemistry. The said compounds may be prepared using the process as described in below scheme.

Scheme I:

Scheme I illustrates the preparation of a compound of formula (I) wherein Q, Ri and R2 are defined as above and Li and L2 represent X or leaving groups. X may be a leaving group which is either the same as that of Li or L2 or other than that of Li and L2. X may also be a group that can be easily substituted by or converted to -CORi.

In the present embodiment, the leaving group LI, L2or X is one which can be easily replaced by the desired group or atom. The leaving group may be selected from halogen atoms, alkoxy and sulfonyloxy groups. Examples of sulfonyloxy groups include, but are not limited to, alkylsulfonyloxy groups (for example methyl sulfonyloxy (mesylate group) and trifluorom ethyl sulfonyl oxy (triflate group)) and arylsulfonyloxy groups (for example /- toluenesulfonyloxy (tosylate group) and /-nitrosulfonyloxy (nosylate group)). For the purpose of the present invention L2 and X may be particularly selected from halogens such as bromo, chloro or iodoand a triflate group. The selection of X is well within the understanding and knowledge of the skilled person.

In the above reactions of Scheme I, a compound of formula 1-1 is converted into a compound of formula 1-2 by a displacement reaction of a compound of formula 1-1 with ammonia solution in a suitable solvent, such as water, THF, 1,4-Di oxane, Dimethyl formamide (DMF), Dimethyl sulfoxide (DMSO) or Acetonitrile (ACN), or mixture(s) therefore at a temperature ranging from 45°C to 120°C for 0.5 hours to 20 hours to form a compound of formula 1-2.

A compound of formula 1-2 is converted to a compound of formula 1-3 by reacting a compound of formula 1-2 with a tritiating agent such as trifluoromethanesulfonic anhydride or a halogenating agent in a suitable solvent such as acetonitrile, chloroform or tetrahydrofuran at a temperature ranging from -20° C to the refluxing temperature for a time period between about 1 hour to about 10 hours.

A halogenating agent according to the present invention is a reagent that is a source of halogen. For example, the agent may be a chlorinating agent such as chlorine, thionyl chloride, N-Chlorosuccinimide, Oxalyl Chloride or a brominating agent such as bromine, N- Bromosuccinimide, Carbon Tetrabromide or an iodinating agent such as Iodine, Hydriodic acid or N-Iodosuccinimide. The halogenating agent may be selected according to the knowledge and understanding of skilled person.

A Sonogashira reaction with a compound of formula 1-3 and an acetylene derivativeusing a suitable catalyst provides a compound of formula 1-4. The reaction conditions for a Sonogashira reaction vary depending on the starting material, the solvent and the transition metal catalyst.The reaction conditions are not limited in particular as long as they are similar to the conditions of the present reactions, and the methods well known to those skilled in the art can be used. Examples of preferred solvents include acetonitrile, tetrahydrofuran, 1,4- di oxane, 1,2-dimethoxy ethane, benzene, toluene, xylene, l-methyl-2-pyrrolidone, N,Ndimethylformamideand dimethylsulfoxide, dichloromethane or mixture thereof. The reaction temperature should be a temperature that is sufficient to complete the coupling reaction, and is preferably from room temperature to 100°C. The present reaction can be carried out under an inert gas atmosphere, and also under a nitrogen or an argon gas atmosphere. Under the preferred reaction conditions, this reaction is completed in 1 hour to 24 hours. The transition metal catalyst is preferably a palladium complex. Examples of palladium complexes include, but not limited to palladium(II) acetate, dichlorobis(triphenylphosphine)palladium(ll),tris(dibenzylideneacetone)dipalladium(0)andtet rakis(triphenylphosphine)palladium(0). Furthermore, in the present reaction, a phoshorous chelating agent such astriphenylphosphine, tri-o-tolylphosphine or tri-tert-butylphosphine may be added in order to obtain satisfactory results. Further the reaction may be accelerated using a metal halide or a quaternary ammonium salt or other such salts, preferably copper(I) iodide, lithium chloride, tetrabutylammoniumfluoride or silver(I) oxide. Preferred results can also be obtained in the presence of a base; the base used is not limited in particular as long as it is used in a coupling reaction similar to the present reaction Examples of such bases include, but not limited to diethylamine, triethylamine, N,N-diisopropylethylamine, piperidine and pyridine.

A compound of formula 1-4 can readily undergo 5-endo-dig cyclization in the presence of a base or transition metal catalyst in the presence of a suitable solvent such as alcoholic solvents or THF or DMA to provide a compound of formula 1-5. Exemplarily the base may be selected from Potassium tert-butoxide, Lithium hydride, Lithium Aluminium hydride and n-butyl lithium and the transition metal catalyst may be selected from Palladium and a copper catalyst.

A compound of formula 1-5 can be optionally protected by treating it with a protecting group to provide a compound of formula 1-6.

Exemplarily a compound of formula 1-5 is converted to the corresponding compound of formulaI-6, wherein R3 is benzenesulfonyl or benzyl, by treating the compound of formula I- 5 with benzenesulfonyl chloride, benzylchloride or benzylbromide in the presence of a base, such as sodium hydride or potassium carbonate, and a polar aprotic solvent, such as dimethylformamide or tetrahydrofuran. The reaction mixture is stirred at a temperature between about 0°C. to about 70°C, preferably about 30°C, for a time period between about 1 hour to about 3 hours, preferably about 2 hours.

R3 is a protecting group such as benzenesulfonyl, substituted benzenesulfonyl, methylsulfonyl, benzyl or carbamate protecting groups such as Boc (t-Butyloxycarbonyl) and CBz (carboxybenzyl) or other groups such as benzoyl, iso-butanoyl, acetyl, phenoxy acetyl, 4- (t-butyl)benzoyl, 4-(t-butyl)phenoxyacetyl, 4-(methoxy)benzoyl, 2-(4-nitrophenyl) ethyl oxycarbonyl, 2-(2,4-dinitrophenyl)ethyloxy-carbonyl, 9-fluorenylmethoxycarbonyl, diphenylcarbamoyl or formamidine groups. Particularly preferred are the benzoyl, isobutanoyl, 4-(t-butyl)benzoyl, 2-(4-nitro-i5 phenyl)ethyloxycarbonyl, 2-(2,4- dinitrophenyl)ethyl-oxycarbonyl, 9-fluorenylmethoxycarbonyl, 4-(methoxy)-benzoyl or para- (t-butyl)phenoxyacetyl, para-nitrophenyl-2-ethyloxycarbonyl group or2-N-acetyl with the 6- O-diphenylcarbamoyl group.

Compounds of formula 1-5 and 1-6 can be converted to a compound of formula 1-8 and 1-7, respectively in a similar way as the process described for the preparation of a compound of formula 1-3. Compounds of formula 1-8 can be converted into compounds of formula (I) by a process known to the person skilled in the art. Such process may include converting X of formula 1-8 directly to an amide group or via formation of ester, anhydride, aldehyde, ketone, cyanide, acid or any such group which can be converted to an amide group which is well within the understanding and knowledge of the skilled person.

For example, when X is converted to an ester group and successively converted to an amide, compounds of formula I-8can betreated withan esterifying agent in the presence of a base in a polar aprotic solvent like THF, 1,4-Dioxane, DMF, DMSO and ACN at -75°C to 100°C temperature for 0.5 hour to 20 hours which leads to formation of ester derivative. The ester derivative on reaction with a trialkylaluminium (like, trimethylaluminium) and required amine derivatives or ammonia solution in the presence of solvents like Toluene, chloroform, methanol, ethanol, THF, 1,4-Dioxane, DMF, DMSO and ACN at -10°C to 100°C temperature for 0.5 hour to 20 hours gives an amide having formula I.

A compound of formula 1-7 can be converted to a compound of formula 1-9 using a similar process that may be used for conversion of a compound of formula 1-8 to a compound of formula I.

A compound of formula 1-9 can be converted into a compound of formula I by cleaving the protecting group R3. Protecting groups of a compound of formula 1-9 can be cleaved by deprotecting agents as understood by the skilled person to obtain a compound of formula I. Examples of deprotecting agents for an amino protective group are acids such as trifluoroacetic acid, trichloroacetic acid, dichloroacetic acid p-toluenesulfonic acid or bases such as alkali or alkaline bases. For example, for a compound of formula 1-9 wherein R3 is benzenesulfonyl, the deprotection is carried out by treating 1-9 with an alkali base, such as sodium hydroxide or potassium hydroxide, sodium carbonate, potassium carbonate, potassium tert-butoxide, sodiumtert-butoxide in an alcohol solvent, such as methanol or ethanol, or mixed solvents, such as alcohol/tetrahydrofuran or alcohol/water. The reaction is carried out at room temperature or to reflux temperature for a time period between about 15 minutes to about 1 hour, preferably 30 minutes. When R3 is benzyl, deprotection is either conducted by treating 1-9 with sodium in ammonia at a temperature of about -78° C for a time period between about 15 minutes to about 1 hour or by using hydrogen and a catalyst, such as palladium hydroxide on carbon, Pd/C, Raney Nickel, Raney Nickel in combination with NH2-NH2 or Hydrogen. Other suitable deprotecting agents are Lewis acids, such as, for example boron trifluorideetherate or zinc bromide in dichloromethane/isopropanol, aq. HC1, aq. HBr, HBr in acetic acid, sulfuric acid. In another embodiment of the present disclosure, it is envisaged to prepare the compound of Formula I including compounds given in Table I. The skilled person in the art may prepare the said compound by using any of the known methods in chemistry. The said compounds may be prepared using the process as described in below scheme.

Scheme II:

Scheme II also illustrates the preparation of a compound of formula (I) wherein Q, R1 R2, R3 and X as defined in aforementioned embodiment. R represents alkoxy (-OR) or CX3, Z is NO2.

In the above reactions of Scheme II, a compound of formula I- 10 can be converted to the corresponding compound of formula 1-11, by treating the compound of formula 1-10 with protecting group R3 such as benzenesulfonyl chloride, benzyl chloride or benzylbromide in the presence of a base, such as sodium hydride, potassium carbonate, sodium hydroxide, potassium hydroxide or cesium carbonate or alkyl lithium such as n-butyl lithium, secondary butyl lithium, tertiary butyl lithium or lithium diisopropyl amide. Such reaction may be carried out in solvent such as dimethylformamide, dimethylacetamide, tetrahydrofuran, hexamethylphosphoramide, dimethyl sulfoxide, 1,4-Dioxane, acetonitrile, water, dichloromethane, Toluene, DMSO or mixture(s) therefore. The reaction mixture is stirred at a temperature between about 0°C. to about 70°C., preferably about 10°C, for a time period between about 1 hour to about 10 hours, preferably about 4 hours. R3 is a protecting group defined as above. Compounds of formula 1-11 can be converted to a compound of formula 1-12 by reacting a compound of formula I- 11 with an acylating agent such as trifluoroacetic anhydride, tri chloroacetyl chloride , acid halides, acid anhydrides in a suitable solvent such as acetonitrile, chloroform, n-methyl pyrrolidone, toluene, tetrahydrofuran, dimethylformamide, dimethylsulfoxide, dimethylacetamide 1,4-Dioxane chlorinated alkyl or aryl solvents such as dichloromethane or chlorobenzene, di chlorobenzene or di chloroethane or mixture(s) therefore at a temperature ranging from -20°C to the refluxing temperature for a time period between about 1 hour to about 15 hours preferably at 65-75°Cfor 4-5 hours.

A compound of formula 1-12 can be converted to a compound of formula 1-13 by treating compound of formula 1-12 with nitrating agents such as alkyl ammonium nitrate for example, tetrabutyl ammonium nitrate or tetramethyl ammonium nitrate and using trifluoroacetic anhydride in solvents such as dichloromethane, toluene, acetonitrile, tetrahydrofuran, chlorobenzene, nitrobenzene, di chloroethane 1,4-Dioxane, acetonitrile, water, dimethylsulfoxide or mixture(s) therefore, at a temperature ranging from -10°C tolOO°C for a time period between about 1 hour to about 30 hours preferably for 5 hours. A compound of formula I- 13 can be converted to a compound of formula 1-14 by reaction with ammonia or with primary amines such as methyl amine, ethyl amine, isopropyl amine, npropyl amine, isobutylamine or n-butylamine in suitable solvents such as tetrahydrofuran, dichloromethane, 1,4 dioxane, toluene, dimethylformamide, water, alcoholic solvents, DMSO, acetonitrile or mixture(s) thereof at a temperature ranging from -10°C to the refluxing temperature for a time period between about 1 hour to about 25 hours, preferably for 8-10 hours.

A compound of formula 1-14 can be converted to compound of formula 1-15 by reduction of nitro group using metal catalyst such as palladium on carbon, Raney nickel in combination with NH2-NH2 or Hydrogen, iron/ammonium chloride, platinum on carbon, zinc/ammonium chloride, Fe/AcOH or sodium dithionite in suitable alcoholic solvents such as methanol, ethanol or water or cyclic/acyclic ethers such as tetrahydrofuran or 1,4-di oxane or acetonitrile and water or in mixture of suitable alcoholic solvents such as methanol, ethanol, or cyclic/acyclic ethers such as tetrahydrofuran or 1,4-dioxane or acetonitrile and water at temperature ranging from -10°C to reflux temperature, preferably at room temperature for time period of 1 to 10 hours.

A compound of formula 1-15 is optionally converted to compound of formula 1-15 a by treating compound of formula 1-15 with alkylating agents or treating with aldehydes, ketones followed by reduction by the methods known to person skilled in the art. A compound of formula 1-15 or I-15a can be converted to compound of formula 1-16 by cyclization methodsusing reagents such as triethylorthoformate and acid catalyst viz para toluene sulphonic acid or dimethylformamide or formic acid and metal catalyst such as zinc acetate, using solvents such as toluene, halobenzene such as chlorobenzene, 1,2 di chlorobenzene, dimethylformamide, dimethylacetamide, tetrahydrofuran, acetonitrile, 1,4- dioxane, water, acetic acid, formic acid, formamide or mixture(s) thereofat a temperature ranging from room temperature to reflux temperature preferably at 0°C-100°C for period of 1 to 10 hours preferably for 5 hours.

A compound of formula 1-16 can be converted to compound of formula 1-17 by hydrolysis using alkali hydroxide such as sodium hydroxide, potassium hydroxide or lithium hydroxide or aqueous solution thereof or any other reagents as understood by the skilled person in suitable alcoholic solvents such as methanol or ethanol or water or in mixture of suitable alcoholic solvents such as methanol, ethanol, propanol, butanol, iso-butanol or cyclic/acyclic ethers such as tetrahydrofuran or 1,4-Dioxane or acetonitrile and water to obtain a compound of formula 1-17, at a temperature ranging from room temperature to reflux temperature preferably at a temperature 80°C for time period of 30 minutes to 10 hours.

A compound of formula 1-17 can be converted into a compound of formula 1-18 by cleaving the protecting group R3. Protecting groups of a compound of formula 1-17 can be cleaved by deprotecting agents as understood by the skilled person to obtain a compound of formula I. Examples of deprotecting agents for an amino protective group are acids such as trifluoroacetic acid, trichloroacetic acid, di chloroacetic acid p-toluenesulfonic acid, HC1, HBr, H2SO4 or bases such as alkali or alkaline bases. For example, for a compound of formula 1-17 wherein R3 is benzenesulfonyl, the deprotection is carried out by treating 1-17 with an alkali base, such as sodium hydroxide or potassium hydroxide, sodium carbonate, potassium carbonate, cesium carbonate in an alcohol solvent, such as methanol or ethanol, or mixed solvents, such as alcohol/tetrahydrofuran or alcohol/water, MDC, THF, toluene, CAN, water or mixture(s) thereof. The reaction is carried out at room temperature to reflux temperature for a time period between about 15 minutes to about 1 hour, preferably 30 minutes. When R3 is benzyl, deprotection is either conducted by treating 1-17 with sodium in ammonia at a temperature of about -78° C for a time period between about 15 minutes to about 10 hour or by using hydrogen and a catalyst, such as palladium hydroxide on carbon, Pd/C in ether solvents such as tetrahydrofuran and alcohol such as tert-butanol, MDC, THF, toluene, CAN, water or mixture(s) thereof.. Other suitable deprotecting agents are Lewis acids, such as, for example boron trifluorideetherate or zinc bromide in dichloromethane/isopropanol. HC1, HBr, H2SO4.

A compound of formula 1-18 can be converted to compound of formula I by reaction of acid derivative ( Formula 1-18) with chlorinating agent such as thionyl chloride, Oxalylchlorideusing mixture of solvents such as dimethylformamide, dimethyl acetamide, di chloromethane, di chloroethane, tetrahydrofuran, benzene, toluene, halobenzeneviz. 1,2 di chlorobenzene or acetonitrile, at a temperature ranging from 0°C to reflux temperature preferably at 70-80oC for a time period of 0.5 hours to 15 hours preferably for 5.0 hours to form acid chloride derivative. This acid chloride derivative can be converted to desired amide compound of formula -I by reaction with ammonia or suitable primary, secondary amine such as methylamine, ethylamine, n-propylamine, isopropyl amine, isobutylamine, n- butylamine, Cyclopropyl amine, cyclopentyl amine, cyclohexyl amine. Amine can be any primary or secondary alkyl amines for example, "Cl-10 alkyl” is intended to include Cl, C2, C3, C4, C5, C6, C7, C8, C9, and CIO alkyl groups, in solvents such as dichloromethane, di chloroethane, tetrahydrofuran, acetonitrile, 1,4-Di oxane, dimethylformamide, dimethylacetamide or mixture(s) thereof at temperature ranging from 0°C to reflux temperature preferably at room temperature for a time period of 0.5 hours to 10 hours preferably for 5.0 hours.

A compound of formula 1-18 can be converted to a compound of formula I by treating compound of formula 1-18 with ammonia or suitable primary, secondary amine such as methylamine, ethylamine, n-propylamine, isopropylamine, isobutylamine, n-butylamine, Cyclopropyl, cyclopentyl, cyclohexyl, using coupling agents such as PyBOP, EDC. HC1, DCC, HoBt or coupling agents known to person skilled in the art. Amine can be primary or secondary alkylalkyl amines for example , "Cl-10 alkyl” is intended to include Cl, C2, C3, C4, C5, C6, C7, C8, C9, and CIO alkyl groups, in solvents such as dichloromethane, di chloroethane, tetrahydrofuran, acetonitrile, 1,4-Di oxane, dimethylformamide, dimethylacetamide or mixture(s) thereof at temperature ranging from 0 Degree Celcius to reflux temperature preferably at room temperature for a time period of 0.5 hours to 15 hours preferably for 10.0 hours.

A compound of formula (I) or its pharmaceutically acceptable salts can be prepared with or without isolation of intermediates. Isolation of a compound of formula (I) or its pharmaceutically acceptable salts and its intermediates may be carried out by any method known in the art such as cooling, filtration, centrifugation, washing, drying and combination thereof. In an embodiment of the present disclosure, it is envisaged to use compound of Formula (I) or a pharmaceutically acceptable salt or a pharmaceutical composition thereof for prophylactic and/or therapeutic treatment of disease caused by virus(es) from Coronaviridae family including SARS-CoV-2 virus or a mutant thereof, wherein the said compounds are capable of inhibiting the viral entry by blocking SpikeS 1 protein of SARS-CoV-2 with ACE2 and inhibiting or modulating the cytokine storm induced by SpikeS 1 protein or mutant SpikeS 1 proteins (SARS-COV-2 derived) induced cytokine storm in lungs and immune cells. The compound of Formula (I) or a pharmaceutically acceptable salt or a pharmaceutical composition thereof is envisaged to interrupt SARS-CoV-2 entry in cell via AT1R downregulation and to significantly inhibit relevant proteases and hormones in pathogenesis of Covidl9, and also the said compound of Formula (I) or a pharmaceutically acceptable salt or pharmaceutical composition thereof significantly inhibits cytokines such as TNF alpha, RANTES, IL6 and IL8 as compared to control, in lung cells (A549) and immune cells (THP- 1).

During infection COVID-19 virus uses the ACE2 receptor to penetrate the host cell. Binding of coronavirus with ACE2 has been shown to downregulate ACE2, contributing to an increase in angiotensin 2 through ACE, decrease in ACE2 results in a lower conversion of angiotensin to angiotensin 1-7 vasodilator and lesser angiotensin I and angiotensin II will be degraded; thus, their plasmatic concentration gradually increases. Elevations in angiotensin II concentrations and stimulation of AT1R lead to a decrease in the stability of the pulmonary endothelium and an aggravation of respiratory distress. Inhibition of AT1R shows interruption of SARS-COV-2 binding to cells and its entry. Post SARS-COV-2 infection activated immune cells produce an array of cytokines such as TNF-alpha, IL-6, IL8, IFN- gamma referred as cytokine release syndrome. Downregulation or control of these pro- inflammatory markers play key role in reduction of cytokine storm.

In an embodiment of the present disclosure, effect of the compound of Formula I or a pharmaceutically acceptable salt thereof was evaluated on following kinases

• NAK (Numb Associated Kinases) - AAK-1, GAK, STK16

• Other kinases SRC, FYN, ABL1, mTOR

In an embodiment of the present disclosure, effect of compound of Formula I or a pharmaceutically acceptable salt thereof was evaluated for in-vivo studies. Balb/c mice were selected as the Test System as it is commonly reported in literature & inflammatory response is higher in BALB/c mice. BALB/c Mouse is potential animal model system for studying Acute and Chronic virus Infection studies.

The exaggerated immune response induced in the lower respiratory tract against coronaviruses (CoVs), including CoViD-19 (2019-nCoV), appears to contribute to the overwhelming lung damage caused by the disease in comparison to the effect of the direct viral invasion and replication in the host. Given this immense health risk, several drugs have been clinically tested, ranging from antivirals, antibiotics, biologies, and corticosteroids up to antioxidants. Despite massive international initiative to develop SARS-CoV-2 vaccines, there remains an unabated, urgent need for effective pharmacologic interventions that prevent COVID-19 patients from clinical declining towards the need for intensive care and assisted ventilation.

In an embodiment of the present disclosure, compound of Formula I or a pharmaceutically acceptable salt thereof exhibited immunostimulatory and Anti-inflammatory activity in invitro and In-vivo studies. As scope extension of blocking of JAK-STAT3 signaling may also inhibit IL-6-mediated signal transduction.

In an embodiment of the present disclosure, effect of compound of Formula I or a pharmaceutically acceptable salt thereof was investigated to combat SARS-cov-2 spike protein induced inflammation in mice by measuring, proinflammatory cytokine levels in BALF & histopathological investigation of lung tissue.

Coronavirus Disease 19 (COVID-19), the disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The renin-angiotensinaldosterone system (RAAS) is crucial to the homeostasis of both the cardiovascular and respiratory systems. Importantly, SARS-CoV-2 utilises and interrupts this pathway directly, which could be described as the renin-angiotensin-aldosteroneSARS-CoV-2-axis (RAAS-SCoV-axis).

Angiotensin II (Ang II), the primary physiological product of the RMS system, is a potent vasoconstrictor. Angiotensin-converting enzyme (ACE) catalyses the transformation of angiotensin I (Ang I) to Ang II. Ang II elicits its effects by activating two receptors: type 1 angiotensin II (ATI) receptor and type 2 angiotensin II (AT2) receptor. Ang II action through ATI receptor causes a cascade with resultant inflammation, vasoconstriction, and atherogenesis. These effects also promote insulin resistance and thrombosis. Angiotensin receptor blockers are being explored as tentative SARS-CoV-2 Therapeutics. A recent hypothesis suggested that angiotensin receptor 1 (ATI R) inhibitors might be beneficial for patients infected by COVID-19 who experience pneumonia.

In an embodiment of the present disclosure, inhibitory effect of compound of Formula I or a pharmaceutically acceptable salt thereof was tested on expression of ATI R (Angiotensin II Receptor Type 1) in cell lines overexpressing ATI R. The said study was performed using SelectScreen® Pathway Profiling Services at Life Technologies, USA.

Effect of compound of Formula I or a pharmaceutically acceptable salt thereof on ATI R was investigated in cell line overexpressing it using Tango Beta-lactamase (bla) Reporter Technology.

In an embodiment of the present disclosure, it is envisaged to use compound of Formula (I) or a pharmaceutically acceptable salt or a pharmaceutical composition thereof for prophylactic and/or therapeutic treatment of disease caused by virus(es) from Coronaviridae family including SARS-CoV-2 virus or a mutant thereof, wherein the said compoundsare capable ofreducing the effect of an disease caused by Coronaviridae family including SARS- CoV-2 virus or a mutant thereof in a subject in need thereof.

In an embodiment of the present disclosure, the compound of Formula I and its pharmaceutically acceptable salts may be formulated with pharmaceutically acceptable stabilizers, diluents and excipients. As understood by the skilled person in art the suitable form of the composition may be determined by the route of administration of the composition. Therefore the suitable form of the composition may include but is not limited to, injection for intravenous (bolus or infusion), intra-arterial, intraperitoneal, subcutaneous (bolus or infusion), intraventricular, intramuscular, or subarachnoidal route; tablet, capsule, gel, lozenge or liquid for oral ingestion; a solution, suspension or aerosol as sprays for inhalation; gel, spray or cream for topical application; transmucosal composition for administration via oral, nasal or rectal mucosa; by delivery in the form of a transdermal patch, subcutaneous implant, or in the form of a suppository. The compounds may also be formulated in rectal compositions such as suppositories or retention enemas. For buccal administration, the compositions may take the form of tablets or lozenges formulated in conventional manner. The composition may be a vesicular drug delivery system such as, but not limited to bilosomes, liposomes, niosomes, transferosome, ethosomes, sphingosomes, pharmacosomes, multilamellarvesicles, microspheres and the like. In an embodiment of the present disclosure, the compounds of Formula I, its pharmaceutically acceptable salts or a pharmaceutical composition thereof may be administered in a subject via any of the known suitable routes of drug administration. It is further envisaged that the administration of said compounds may provide a means to cure or reduce the effect of Coronaviridae family including SARS-ingCoV-2 virus or a mutant thereof in a subject suffering from disease.

The routes of drug administration include but not limited to intravenous injection (bolus or infusion), intra-arterial, intra-peritoneal, subcutaneous, intraventricular, intramuscular, subarachnoidal, surgical implants, oral ingestion, inhalation, topical, and mucosal (oral, nasal and/or rectal), etc. In a preferred embodiment of the present disclosure, drug may be administered enterally, parenterally and/or topically. Liquid dosage forms for oral administration may include but not limited to emulsions, microemulsions, solutions, suspensions, syrups and elixirs pharmaceutically acceptable. In addition to the active compounds, the liquid dosage forms may contain inert diluents commonly used in the art.Injectable preparations such as aqueous or oleaginous sterile injectable suspensions may be formulated according to known techniques by suitable dispersing or wetting agents and suspending agents commonly used in the art.

In an embodiment of the present disclosure, subject may be ananimal. In preferred embodiment, the subject is mammalian subject. In particular, the mammalian subject may be a human subject infected with or seeking prevention from Coronaviridae, SARS-CoV-2 virus or a mutant thereof. The human subject may be male or female coming from different ethnic groups or race, geographical regions, countries, continents and races. For example, the human subject may be selected from a group comprising of an Asian (e.g., far-east Asian, middleeast Asian, south-east Asian, north-east Asian, or Asian Indian), a Caucasian (Canadian, American, European, or Mediterranean), an African, a pacific islander, a Hispanic, etc or a general mixed population. The said subject may be of any age, including newborn, neonate, infant, child, adolescent, adult, and geriatric, etc.

In an embodiment of the present disclosure, the compounds envisaged to be administered in a subject may comprise of compound of Formula I or combination of one or more salts as disclosed in Table 1. In an embodiments, it is further envisaged to use one or more compounds selected from ‘N-(propan-2-yl)-l,6-dihydroimidazo[4,5-d]pyrrolo[2,3- b]pyridine-8-carboxamide hydrochloride’ and ‘N-(propan-2-yl)-3,6-dihydroimidazo[4,5- d]pyrrolo[2,3-b]pyridine-8-10 carboxamide hydrochloride’ independently or in combination thereof.

In an embodiment of the present disclosure, the compounds envisaged by the present disclosure may be given in form of a prodrug. “Prodrugs” may include any covalently bonded carriers that release an active compound of the present disclosure in vivo when such prodrug is administered to mammalian subject. Prodrugs of the present invention are prepared by modifying functional groups present in the compound in such a way that the modifications are cleaved, either in routine manipulation or in vivo, to give the parent compound. The skilled person in the art is well aware that the prodrugs are known to enhance numerous desirable qualities of pharmaceuticals (e.g. solubility, bioavailability, manufacturing, etc.) and the compounds of the present disclosure may be delivered in prodrug form.

In an embodiment of the present disclosure, the compounds envisaged by the present disclosure may be given at a concentration sufficient to elicit a desired biological response. As understood by the skilled person in art, the concentration of the compound envisaged by the present disclosure may vary depending upon such factors as desired biological endpoint; the pharmacokinetics of the compound, the condition being treated, the mode of administration, age, bodyweight and health of the subject.

In an embodiment of the present disclosure, prophylactic and/or therapeutic treatment of a subject may include administration of an effective concentration of compound of Formula I or a pharmaceutically acceptable salt thereof. As understood by the skilled person in art, the effective concentration of the compound of Formula I or a pharmaceutically acceptable salt thereof may be determined using pharmacokinetics and pharmacodynamic studies. Particularly, the compound of Formula I or a pharmaceutically acceptable salt thereof may be administered at a concentration in the range of 0.01 to 1000 milligram per kilogram of subject’s body weight. In certain ways of embodiment, the compounds of the disclosure may be administered as such or in a pharmaceutically acceptable form orally or parenterally at dosage levels of about 0.01 to lOOOmilligram per kilogram, from 0.1 to lOOmilligram per kilogram, from 0.5 to 100 milligram per kilogram or from 1 to 50 milligram per kilogram of the subject's body weight per day, once or several times per day, to obtain the desired therapeutic effect. EXAMPLES

The following examples are provided to illustrate the invention. Examples provided herein are exemplary in nature and do not limit the scope of invention in any manner.

Example 1: Preparation of N-(propan-2-yl)-l,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b] pyridine-8-carboxamide hydrochloride

Ethanolic hydrochloride solution was added to the solution of N-(propan-2-yl)-l,6- dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide (10 mmol) in 50 mL ethanol. The reaction was stirred for 3-4 hours at ambient temperature. Reaction mass was concentrated under reduced pressure. 10 ml ethanol was added to the residue, stirred and reaction mass was concentrated under reduced pressure. Obtained solid was dried under vacuum to afford white to off while solid of the title compound (Yield = 95%).

15 1H NMR (400 MHz, DMSO-D6) 8: 1.25 (d, 6 H), 4.23 (m, 1 H), 7.99 (s, 1 H), 8.34 (s, 1H), 8.57 (s, 1H),8 8.7 (bslH), 11.2 (br. S, 1H), 12.9 (br. S, 2H).

Preparation of an Intermediate:6-benzyl-N,l-dimethyl-l,6-dihydroimidazo[4,5- d]pyrrolo[2,3-b]pyridine-8-carboxamide

Step A: 6-benzyl-l-methyl-l,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine

In a round bottom flask, sodium hydride (0.3 mole) was added in a DMF (5 vol) solvent, 1- methyl-l,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine (0.1 mole) was slowly added at 5- 15°C to a flask, the resulting suspension was stirred at room temperature for 1 hour, then benzyl bromide (0.12 mole) was slowly added at 5-15°C. The reaction mass was warmed to room temperature and stirred for 1-3 hours. The reaction was monitored on TLC. The reaction mass was cooled after completion of the reaction, methanol (1 vol ) was added in the reaction mass at 5-15°C and stirred for 10 min. Ammonium chloride (25 vol) solution was added in the reaction mass and stirred for 30 min. The reaction mass was extracted with ethyl acetate (3* 5 vol). Combined organic layers were washed with water (3* 5 vol) and brine (Ivol), then dried over magnesium sulfate, filtered and concentrated in vacuo to provide the title compound (86%).

Step B: 6-benzyl-8-bromo-l-methyl-l,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine

6-benzyl-l-methyl-l,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine (1 mmol) was dissolved in THF (25 mL) at room temperature and to the resulting solution was added Nbromosuccinimide (1.2 mmol). The resulting suspension was stirred at room temperature for 14 hours, then quenched with aqueous saturated sodium thiosulfate solution (20 mL). The reaction was concentrated in vacuo, and the resulting residue was diluted with ethyl acetate (75 mL). The aqueous layer was extracted with ethyl acetate (2*100 mL) and the combined organic layers were washed with aqueous IN sodium bicarbonate solution (50 mL) and brine (50 mL), then dried over magnesium sulfate, filtered and concentrated in vacuo to provide title compound (87%), which was used further with or without purification.

Step C: ethyl 6-benzyl-l-methyl-l,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8- carboxylate

6-benzyl-8-bromo-l -methyl- l,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine (173 mmol) was added in dry tetrahydrofuran (500 mL) at -78 °C and n-butyl lithium (2.5 M solution in hexane, 487 mmol) was added over a period of 2 hours. The reaction mixture was stirred for another 30 minutes at -78 °C. Ethyl chloroformate (186 mmol) was added over 30 minutes and the reaction mixture was stirred for 2 hours at -60 °C. The temperature was slowly increased to 30 °C and mixture was allowed to stir for 12 hours at 30 °C. The progress of the reaction was monitored by TLC. The reaction mixture was then quenched with saturated solution of ammonium chloride (150 mL) at 0 °C and the reaction mixture was extracted with ethyl acetate (3X300 mL). The combined organic layers were washed with water, dried over anhydrous sodium sulfate (50 g), filtered and concentrated under reduced pressure to afford a crude reaction mixture. The residue was purified by chromatography to provide the title compound (50%).

Step D: 6-benzyl-N,l-dimethyl-l,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8- carboxamide

A solution of trimethylaluminium (2 M in toluene, 1.2 mmol) was added dropwise (exothermic) to a solution of methylamine (2 M in toluene, 1.2 mmol) in dioxane (7.5 mL) and the resulting mixture was stirred at room temperature for 1 h. Then a solution of ethyl 6- benzyl-l-methyl-l,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxylate (0.3 mmol) in dioxane (4 mL) was added. The resulting mixture was then heated at 85-95° C. for 3 h and then cooled to room temperature and then poured into water and extracted with MDC which was then washed with brine, dried over sodium sulfate and evaporated. Purification by chromatography (SiO2, MDC:MeOH=90:10) afforded the title compound as a white solid. (70%).

Example 2:Preparation of N-(propan-2-yl)-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3- b]pyridine-8-carboxamide hydrochloride

Step A: l-(l-benzyl-4-chloro-lH-pyrrolo[2,3-b]pyridin-3-yl)-2,2,2-trifluoroethanone

To a stirred suspension of sodium hydride (39.3 g, 1638.5 mmol, 60%) in dimethylacetamide (500mL) was added a solution of 4-chloro-7-aza indole (100g, 655.4 mmol) in dimethylacetamide (150 mL) at 0-5°C followed by benzyl bromide ( 134.5 gm, 786.5mmol). The resultant reaction mixture was stirred for 4.0 hours and then quenched with 100 ml of methanol followed by saturated ammonium chloride (500mL) and extracted with ethylacetate. The organic layer was evaporated under reduced pressure to afford brown to yellow color liquid, l-benzyl-4-chloro-lH-pyrrolo [2,3-b]pyridine (180 gm). The above compound was dissolved in in dimethylformamide (700 mL) and then was added trifluoroacetic anhydride (129.8 g, 618.0 mmol). The resulting reaction mixture was heated at 70-75°C for 3.0 hours. Reaction mixture was cooled to 10-15°C and was added ice cold water (500 mL) followed by saturated aqueous sodium bicarbonate. Reaction mixture was filtered and purified by using Isopropanol to obtain beige to light yellow color solid 1-(1 -benzyl -4- chloro-lH-pyrrolo[2,3-b]pyridin-3-yl)-2,2,2-trifhioroethanone, (125.0 g 89.6%).

1HNMR (400 MHz, DMSO-d6): 8 9.03 (S,1H), 8 8.38 (m 1H), 8 7.46 (m, 1H), 8 7.34(m,5H), 8 5.66 (S,2H).

Step B: l-(4-amino-l-benzyl-5-nitro-lH-pyrrolo[2,3-b]pyridin-3-yl)-2,2,2- tri fluoroethanone

To a stirred solution of l-(l-benzyl-4-chloro-lH-pyrrolo[2,3-b]pyridin-3-yl)-2,2,2- trifluoroethanone (100 g, 295.2 mmol) in di chloromethane (2500mL) was added tetrabutylammonium nitrate ( 224.7 g, 738.0 mmol) in portions followed by dropwise addition of trifluoroacetic anhydride (155 g, 738.0 mmol) at 0°C. The reaction mixture was stirred for 5.0 hours at room temperature. Organic layer was washed with water and concentrated under reduced pressure to afford yellowsolid, l-(l-benzyl-4-chloro-5-nitro- lHpyrrolo[2,3-b]pyridin-3-yl)-2,2,2 trifluoroethanonene (100 gm 88.5%).

To a stirred solution of l-(l-benzyl-4-chloro-5-nitro-lH-pyrrolo [2,3 -b]pyri din-3 -yl)-2, 2,2- trifluoroethanone (100 g, 260.6mmol) in di chloromethane (500 mL) was purged ammonia gas till completion of reaction on TLC. Solvent was removed under reduced pressure. The residue was dissolved in dichloromethane (300 ml) , cooled to 5-10°C and filtered. The obtained wet solid was dried under vacuum to afford yellow solid, l-(4-amino-l-benzyl-5- nitro-lHpyrrolo[2,3-b]pyridin-3-yl)-2,2,2-trifluoroethanone (85gm ,89.5%) 1HNMR (400 MHz, DMSO-d6): 8 9.04 (S,1H), 8 8.94(m 1H), 8 8.73 (S, 1H), 8 7.30 (m,6H), 8 5.57 (S,2H).

Step C: l-(4,5-diamino-l-benzyl-lH-pyrrolo[2,3-b]pyridin-3-yl)-2,2,2-trifluoroethanone

To a stirred solution of l-(4-amino-l-benzyl-5-nitro-lH-pyrrolo[2,3-b]pyridin-3-yl)-2,2,2- trifluoroethanone (85 g, 233.3 mmol) in mixture of methanol: tetrahydrofuran (1500 mL, 1 :0.5) was added Raney Nickel (21.2 g 25.0 % w/w) followed by dropwise addition of hydrazine hydrate ( 59.5 ml, 0.70 w/v) and reaction mixture was stirred for 1.0 hours at room temperature. After completion, reaction mixture was filtered through hyflo bed and washed with methanol (400 mL). The filtrate was concentrated under reduced pressure and obtained was purified by water (500 mL), filtered and dried under reduced pressure to afford brown color solid l-(4,5-diamino-l-benzyl-lH-pyrrolo[2,3-b]pyridin-3-yl)-2,2,2-trifluoroethanone (71.0gm 90.8%) 1HNMR (400 MHz, DMSO-d6): 8 8.59 (d,lH), 8 7.66 (s 1H), 8 7.33 (m, 4H), 8 7.26 (m,lH), 8 6.56 (s,2H), 8 5.45 (s,2H), 8 4.47 (s,2H).

Step D: l-(6-benzyl-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridin-8-yl)-2,2,2- tri fluoroethanone

To stirred suspension of l-(4,5-diamino-l-benzyl-lH-pyrrolo[2,3-b]pyridin-3-yl)-2,2,2- trifluoroethanone (70g, 209.4 mmol) in toluene (700 mL) was added triethylorthoformate (96.7 mL, 418.8 mmol) and para-toulenesulfonic acid monohydrate (8.0 g 41.88 mmol). The resulting reaction mixture was heated at 80-85°C for 5.0 hours. After completion, reaction mixture was concentrated under reduced pressure. To the obtained residue was added water (700 mL), stirred at room temperature and filtered an dried to afford l-(6-benzyl-3,6- dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridin-8-yl)-2,2,2-trifluoroethanone (65gm, 90.1%). 1HNMR (400 MHz, DMSO-d6): 8 12.51(bs,lH), 8 8.89 (m 2H), 8 8.29 (t, 1H), 8 7.31 (m,5H), 8 5.72(s,2H).

Step E: 6-benzyl-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxylic acid

To the solution of sodium hydroxide (151gm, 3775 mmol) in water ( 945 mL) was added 1- (6-benzyl-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridin-8-yl)-2,2,2 trifluoroethanone (65 gm, 188.8 mmol), reaction mass was heated at 80-85°C for 5.0 hours. After completion, reaction mixture was diluted with water followed by dilute HC1 and filtered. The obtained wet cake was dried under vacuum to afford beige to light brown color solid 6-benzyl-3,6- dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8- carboxylic acid, (50gm,90.5% ) 1HNMR (400 MHz, DMSO-d6): 8 12.2(s,lH), , 8 8.75(s, 1H), 8 8.22(s,lH),8 8.17 (s, 1H) 8 7.27(m,5H), 8 5.61(s,2H) Step F: 3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxylic acid

To the solution of liquid ammonia (750 mL) was added sodium metal (32.8 g, 1368.5mmol) lot wise. To the resulting reaction mixture, was added tertiary butanol (50 mL), Tetrahydrofuran (500 mL) followed by 6-benzyl-3,6-dihydroimidazo[4,5-d] pyrrolo [2,3- b]pyridine-8-carboxylic acid (50 g, 171.1 mmol). Then reaction mixture was stirred at -60°C to -30°C for 4.0 hours and quenched with methanol (50 mL) and water (50 mL). Solvent was evaporated under reduced pressure. Then was added water (100 ml) to the residue followed by HC1 and stirred. The reaction mixture was filtered and wet solid was dried under reduced pressure to afford beige color solid 3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8- carboxylic acid, (32gm,91.4%).

1HNMR (400 MHz, DMSO-d6): 8 12.39 (bs,lH), 8 12.07 (bs 1H), 8 8.66(s, 1H), 8 8.14(d,lH), 8 7.94 (s,lH).

Step G: N-(propan-2-yl)-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8- carboxamide

To a solution of 3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxylic acid (30.0 g, 148.4 mmol) in dimethylformamide (15 mL) was added thionyl chloride (300 mL) and reaction mixture was heated to 65-70°C and stirred for 4.0 hours. After completion, reaction mixture was concentrated under reduced pressure to obtain acid chloride (30 g) which was used as such for further reaction. Above acid chloride derivative(30 g) was taken into dichloromethane (300 mL), cooled to 5-10°C and added isopropyl amine (300 mL). The resulting reaction mixture was stirred for 5.0 hours at room temperature. After completion, reaction mass was concentrated under reduced pressure, added water (150 mL) and filtered. The obtained wet solid was dried under vacuum to afford beige to off white color solid N- (propan-2-yl)-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide (29.0gm,80.3%) 1HNMR (400 MHz, DMSO-d6): 8 13.04 (bs,lH), 8 12.19 (t, 1H), 8 10.03(d,lH), 8 8.59(d,2H), 8 8.07(m,lH), 8 4.19(m,lH), 8 1.22(td,6H).

Step H: N-(propan-2-yl)-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8- carboxamide hydrochloride

To a solution of N-(propan-2-yl)-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8- carboxamide ( 25.0 g, 102.8 mmol) in isopropanol( 175 mL) was added solution of HC1 in isopropanol at 10-15°C. The resultant reaction mixture was stirred at 50-55°C 2.0 hours. After completion, reaction mixture was concentrated under reduced pressure. To the residue obtained was added water (250 mL) and stirred for 1.0 hour at room temperature, filtered and dried under vacuumto afford beige color solid N-(propan-2-yl)-3,6-dihydroimidazo[4,5- d]pyrrolo[2,3- b]pyridine-8-carboxamide hydrochloride, (25 gm, 87.0%).

1HNMR (400 MHz, DMSO-d6): 8 13.66 (bs,lH), 8 12.87(bs, 1H), 8 9.26(s,lH), 8 8.86(s,lH), 8 8.57(d,2H),84.81 (bs 1H), 8 4.22(qd,lH), 8 1.25(d,6H).

Example 3: Effect of test compound on inhibition of binding of SpikeSl protein with ACE2 protein

N-(propan-2-yl)-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3- b]pyridine-8-carboxamide hydrochloride was used as a test compound for evaluation.

Effect of test compound on binding of SpikeSl protein to ACE2 was evaluated using SARS- CoV-2 Spike-ACE2 Interaction Inhibitor Screening Assay kit.

In a Rabbit Fc-tagged SARS-CoV-2 Spike SI RBD pre-coated 96-well, immunoassay buffer (provided in kit), different concentrations of test compound, positive control and ACE2 Inhibitor Screening reagent were incubated. Further, Spike Inhibitor screening reagent was added to plate and incubated. Finally, the plate was treated with Anti-His-HRP Conjugate, followed by addition of TMB Substrate to produce color.

Inhibition of binding was determined in comparison with control (i.e. well without Test Compound/ Positive Control). Results show that test compound demonstrated significant inhibition of SpikeS 1-ACE2 binding as compared to control.

Example ^Determination of Non-Cytotoxic Doses of test compound

A549 cells were plated in DMEM +10% FBS at a density of 10,000 cells/ well in 96-well culture plates and incubated at 37°C for 24 h. THP-1 cells were plated in RPMI +10% FBS at a density of 10,000 cells/ well in 96-well culture plates and incubated at 37°C for 24 h. Cells were sera-starved for 24h. Next day, cells were treated with Test compoundat different concentrations ranging from 0.1pM-50pM. Untreated cells were used as control. Cells treated with dexamethasone, hydroxychloroquine and Tofacitinib were included as positive control. After treatment, cells were incubated in a 5% CO₂ incubator for 48 h. Effect oftest compound on cell viability was estimated by 3-(4, 5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay.

Example 5: Determination of Cytokine Levels by ELISA

N-(propan-2-yl)-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3- b]pyridine-8-carboxamide hydrochloride was used as a test compound for evaluation. A549 and THP-1 cells were counted using a hemocytometer and plated in a tissue culture plate at the density of 0.1 x 10⁶ cells/well in 24 well plate in growth medium supplemented with 10% FBS. The above cells were incubated at 37°C in 5% CO2 incubator for 24 hour. Cells were sera starved for 24 h. Cells were treated withTest compoundat different concentrations ranging from 0.1pM-50 pM and stimulated with mutant SpikeS 1 proteins (SARS-COV-2 derived) for 48 hour. Cells treated with Dexamethasone and Hydroxychloroquine and stimulated with mutant SpikeS 1 protein (SARS-COV-2 derived) were included as positive controls. Cells stimulated with mutant SpikeS 1 protein (SARS- COV-2 derived) alone were included as control. Untreated cells were included as Negative control. After 48 hour, cell culture supernatants were collected from each well and stored at - 20°C till analysis. The levels of inflammatory markers were determined by ELISA as follows: Assay diluent was added to each well. Respective kit standards and samples (supernatants of cells) were directly pipetted into the wells and incubated for 2 hour at RT. After washing away any unbound substances for a total of 5 times, respective conjugate was added to each well and incubated for 1-2 hour at RT. Following a wash (5 times) to remove any unbound conjugate, substrate solution was added to the wells and incubated for 30 min at RT in dark. The reaction was stopped by adding Stop solution to each well.

The optical density of the color was measured at 450 nm. The percent inhibition in each sample was determined as follows:

[{Concentration of Cytokines (pg/ml) in Control cells (stimulated with mutant spike protein alone) - Concentration of Cytokines (pg/ml) in test compound + Mutant Spike protein treated cells}/ Concentration of Cytokines (pg/ml) in Control cells (stimulated with mutant spike protein alone)] *100.

Example 6:

Evaluation of Inhibitory Effect of test compound on Proteases Relevant in Covid-19 Using Cell Free Assays Inhibitory effect of test compoundon different proteases relevant in Covid- 19 was studied using specific cell-free, enzymes-based assay kits. N-(propan-2-yl)-3,6-dihydroimidazo[4,5- d]pyrrolo[2,3- b]pyridine-8-carboxamide hydrochloride was used as a test compound for evaluation. CATHEPSIN L Inhibitor Screening Assay

• Reagents were added as below in the same order as mentioned:

• After the addition of substrate solution, reaction mix was incubated at room temperature for 60 minutes.

• Fluorescence was read at (excitation = 360 nm; emission = 460 nm) in microplate reader. Decrease in fluorescence indicated inhibition of the Cathepsin L.

• Inhibition of Cathepsin L was calculated as:

% Inhibition — [(RFU Enzyme control “ RFU TI/Pc)/ RFU Enzyme control] * 100

3CL Protease, MBP-tagged (SARSCoV-2) Assay

• Reagents were added as below in the same order as mentioned:

• After the addition of substrate solution, reaction mixture was incubated at room temperature for overnight.

• Fluorescence was read at (excitation = 360 nm; emission = 460 nm) in microplate reader.

Decrease in fluorescence indicated inhibition of the 3 CL.

• Inhibition of 3CL was calculated as:

% Inhibition [(RFU Enzyme control “ RFU TI/Pc)/ RFU Enzyme control] * 100

DPP4 Assay

• Reagents were added as below in the same order as mentioned:

• After the addition of substrate solution, reaction mixture was incubated at room temperature for 10 minutes.

• Fluorescence was read at (excitation = 360 nm; emission = 460 nm) in microplate reader. Decrease in fluorescence indicated inhibition of the DPP4.

• Inhibition of DPP4 was calculated as:

% Inhibit! on= [(RFU Enzyme control ' RFU _T|/|>_C)/ RFU Enzyme control] * 100

TMPRSS2 Assay

• Reagents were added as below:

• After the addition of substrate solution, reaction mix was incubated at room temperature for lOmin.

• Fluorescence was read at (excitation = 383 nm; emission = 455 nm) in microplate reader. Decrease in fluorescence indicated inhibition of the TMPRSS2.

• Inhibition of TMPRSS2 was calculated as:

% Inhibition— [(RFU Enzyme control “ RFU TI/Pc)/ RFU Enzyme control] * 100

Example 7:

Evaluation of virucidal activity of test compound against coronavirus (SARS-COV-2)

Virucidal effect of the test item against coronavirus (SARS-COV-2) was determined. Total destruction of the host cell monolayer is the most severe type of Cytopathic effect. To observe this process, cells were seeded on a glass surface and a confluent monolayer of host cell was formed. Then, the virus pre-incubated with test item was introduced, and viability was measured by using viability dye.

In vitro virucidal activity of Test Item was determined in CPE based method in an anti- SARS-CoV-2 assay in host cells such as Vero76 cells using a Reed-Muench method.

Test Item and virus were kept in contact with each other at room temperature as follows: Table -10 - Details of contact time and dilution used of Test Item

The Virucidal activity was reflected by LRV values of Test Item.

Table 11: Virucidal efficacy of Test Item against SARS-CoV-2 after a contact with virus at room temperature

a Toxicity indicates the highest dilution of the endpoint titer where full (80-100%) cytotoxicity was observed. b Neutralization control indicates the highest dilution of the endpoint titer where compound inhibited virus CPE in wells after neutralization (ignored for calculation of virus titer and LRV) c Virus titer of test sample or virus control (VC) in loglO CCID50 of virus per 0.1 mL d LRV (log reduction value) is the reduction of virus in test sample compared to the virus control(VC titer - Virus titer of sample).

Example 8:

Evaluation of inhibitory effect of Test item on nak (numb associated kinases) and other kinases

N-(propan-2-yl)-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3- b]pyridine-8-carboxamide hydrochloride was used as a test compound for evaluation. Coronavirus disease 2019 (COVID-19) is an infectious disease caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). COVID-19 is highly contagious disease that mainly effect the lungs and leads to generation of inflammatory cytokines and chemokines. Various JAK inhibitors are being explored clinically in the management of SARS-COV2 infection, such as, Olumiant (Baricitinib), Jakafi (Ruxolitinib), Xeljanz (Tofacitinib). Host kinase inhibitors represent one category of compounds with a great potential to be repurposed as broad-spectrum antivirals. Viruses hijack a large number of host kinases at distinct steps of their life cycle. Efforts are being made by various research groups to determine the therapeutic potential and biological rationale of repurposing already approved kinase inhibitors as antivirals.

Effect on following kinases was observed:

• NAK (Numb Associated Kinases) - AAK-1, GAK, STK16

• Other kinases SRC, FYN, ABL1, mTOR

Hence in the present study, inhibitory effect of Test Item was tested on NAK kinases and other kinases pathways.

TABLE 12 - Inhibitory effect of Test Item on NAK and other kinases

Percentage inhibition wrt Control

Statistical Significance

TABLE 13 - IC50 values of Test Item for inhibition of NAK and other kinases

Example 9:

Effect of Test Item to combat SARS-COV-2 spike protein induced lung inflammation in mice. EP157/21

Balb/c mice selected as the Test System as it is commonly reported in literature & inflammatory response is higher in BALB/c mice. BALB/c Mouse is potential animal model system for studying Acute and Chronic virus Infection studies.

Test Item also exhibited immunostimulatory and showed Anti-inflammatory activity in invitro and In-vivo studies. As scope extension of blocking of JAK-STAT3 signaling might also inhibit IL-6-mediated signal transduction. The current study was planned to investigate Test Item to combat SARS-cov-2 spike protein induced lung inflammation in mice. Objective of the study is to evaluate potential of Test Item to combat SARS-Cov-2 Spike protein induced inflammation in mice by measuring, proinflammatory cytokine levels in BALF & histopathological investigation of lung tissue.

Animals were distributed into following 4 experimental groups n=8 animals/group. Gl: Normal control, G2-SARS-Cov-2 group, G3-Standard-Dexamethasone O.lmg/kg oral, G4- Test Item 24 mg/kg Oral. Animals were given pre-treatment for 3 days from Dayl to Day3. Gl and G2 animals received vehicle 5ml/kg Oral. Group 3 animals were administered Dexamethasone at O. lmg/kg orally. Group 4 animals were received Test Item at dose of 24 mg/kg orally. During experimental period daily body weight, clinical sign and Rectal Temperature of animals were measured.

OBSERVATIONS

Body Weight Body weight of each animal was recorded once daily during the experiment. Mean body weight was calculated and represented in tabular and graphical form. % change in body weight of the animals calculated by using formula.

% Body Weight Change =

{(Mean B. wt. at day x - Initial Mean B.wt)/ Initial Mean B.wt } 100

Mean body weight of the groups were Expressed in Mean and SEM on respective days. Nonsignificant G2-SARS Cov-2 group compared to Gl-Normal control group and Nonsignificant Treatment groups compared to G2 SARS-Cov-2 group

% Change BW of the groups were Expressed in Mean and SEM on respective days. Nonsignificant G2-SARS Cov-2 group compared to Gl-Normal control group and Nonsignificant Treatment groups compared to G2 Arthritis group. Clinical sign

Animals were observed for detailed clinical sign including abnormal breathing, dyspnea, aggression, Hypothermia, Secretions, Hyperactivity etc.

Animals were observed for clinical signs such as including abnormal breathing, dyspnea, aggression, Hypothermia, Secretions, Hyperactivity etc daily throughout the experimental period.

_ l=Normal, 3=Abnormal breathing, 45-Hypothermia

Rectal Temperature

Animals’ rectal temperature was monitored using digital probe thermometer. Mean body temperature were calculated to represent suitably. During the experimental period, body temperature of the animals was measured by using rectal probe. Mean Rectal temperature of all the groups were calculated and compared withing groups.

Table 18 : Rectal Temperature

Biomarker analysis

BALF was used for following cytokine/biomarker analysis using ELISA method as per manufacturers instruction. • Interleukin-6 (Cat#MBS175960, Lot#1321671827)

• Interleukin- la (Cat#MBS761122, Lot#M0108F106)

• MCP-1 (Cat#MBS175778, Lot#27qw315114123A1019)

• IFN-/Cat#MBS175777, Lot#9715128616A1019)

% increase vs G1 (Disease induction) and % Decrease of treatment groups were calculated by following formulas:

% Induction (increase) of Disease =

{(Disease (Mean Value G2) - Normal control/ Normal control} *100 % Inhibition =

{(Disease (Mean Value G2) -Treatment)/ (Treatment -Normal control} * 100

Histopathology

After BALF collection, lungs were by administering 0.5 ml of 10% NBF and then stored in stored in 10% Neutral buffered Formalin. After Formalin fixed tissues were processed and embedded in paraffin and sectioned to approximately 5 pm thickness using a microtome and stained with hematoxylin and eosin (H&E) for pathological evaluation.

In histopathological investigation, each lung was scored in the scale of 0-4 for Neutrophilic infiltration and Interstitial edema. Mean score was calculated for each group and compared.

Example 10:

Evaluation of inhibitory effect of Test Item on angiotensin receptor

N-(propan-2-yl)-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide hydrochloride was used as a test compound for evaluation. Effect of Test Item on the expression of AT1R was evaluated in AGTRl-blaU20S cells.

The present disclosure has been made with reference to various embodiments and techniques. However, one skilled in the art will understand that many variations and modifications may be made while remaining within the scope of the disclosure as defined in the appended claims.

Claims

We Claim: . A compound of Formula (I)

or a pharmaceutically acceptable salt thereof; wherein Q is a group of formula QI or Q2;

Q¹ Q2

(_Wavy bond) represents the points of attachment; wherein Ri is -NR^aR^b;

R2 is hydrogen or a C1-C10 alkyl group; and

R^a and R^b independently represent hydrogen or a C1-C10 alkyl group; for use in the treatment or prevention of an infectious disease caused by Coronaviridae or a mutant thereof. . The compound for use according to claim 1, wherein Q is QI and R2 represents hydrogen or a C1-C10 alkyl group. . The compound for use according to claim 1, wherein Q is Q2 and R2 represents hydrogen or a C1-C10 alkyl group.

4. The compound for use according to any one of claims 1 to 3, wherein Riis -NHR^a.

5. The compound for use according to any one of claims 1 to 3, wherein Riis -NHR .

6. The compound for use according to any one of claims 1 to 3 , wherein R is methyl.

7. The compound for use according to any one of claims 1 to 3 , wherein Riis hydrogen.

8. The compound for use according to any one of claims 1 to 5, wherein R^a is methyl, R^b is hydrogen and R2 methyl.

9. The compound for use according to any one of claims 1 to 5, wherein R^a is ethyl, R^b is hydrogen and R2 methyl.

10. The compound for use according to any one of claims 1 to 5, wherein R^a is propyl, R^b is hydrogen and R2 methyl.

11. The compound for use according to any one of claims 1 to 5, wherein R^ais isopropyl, R^b is hydrogen and R2 methyl.

12. The compound for use according to any one of claims 1 to 5, wherein R^a is methyl, R^b and R2 are hydrogen.

13. The compound for use according to any one of claims 1 to 5, wherein R^a is ethyl, R^b and R2 are hydrogen.

14. The compound for use according to any one of claims 1 to 5, wherein R^a is propyl, R^b and R2 are hydrogen.

15. The compound for use according to any one of claims 1 to 5, wherein R^a is isopropyl, R^b and 2 are hydrogen.

16. The compound for use according to claim 1 wherein the compound of Formula (I) is selected from the group consisting of:

N, 1 -dimethyl- 1 ,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide;

N-ethyl-l-methyl-l,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide; l-methyl-N-propyl-l,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide;

1 -methyl-N-(propan-2-yl)- 1 ,6-dihydroimidazo[4,5-d]pyrrolo [2,3 -b]pyridine-8- carboxamide;

N-methyl-l,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide;

N-ethyl-l,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide;

N-(propan-2-yl)-l,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide;

N,3-dimethyl-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide;

N-ethyl-3-methyl-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide; 3-methyl-N-propyl-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide;

3-methyl-N-(propan-2-yl)-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8- carboxamide;

N-methyl-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide;

N-ethyl-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide; and N-(propan-2-yl)-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide; or a pharmaceutically acceptable salt thereof.

17. The compound for use according to claim 1, wherein the compound of Formula (I) is selected from the group consisting of: N-(propan-2-yl)-l,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide hydrochloride; and N-(propan-2-yl)-3,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridine-8-carboxamide hydrochloride.

18. The compound for use according to claim 1, wherein the compound inhibits the viral entry in a cell by blocking SpikeS 1 protein of SARS-CoV2 from binding with ACE2 receptors.

19. The compound for use according to claim 1, wherein the compound modulates the cytokine storm induced by SpikeS 1 proteins of coronaviridae or a mutant thereof by inhibition of cytokines such as IL-6 and IL-8.

20. The compound for use according to claim 1, wherein the compound interrupts SARS- CoV-2 entry in a cell by: a) AT 1 R downregulation, or b) Inhibition of proeases such as Cathepsin L, 3CL, DPP4.

21. A pharmaceutical composition comprising a compound of Formula (I) as defined in any one of the preceding claims or a pharmaceutically acceptable salt thereof for use in the treatment or prevention of an infectious disease caused by Coronaviridae or a mutant thereof.

22. The compound for use according to any one of claims 1 to 17 or a composition for use according to claim 21, wherein the infectious disease caused by Coronaviridae or a mutant thereof is a disease caused by SARS-CoV-2 or a mutant thereof.

23. The method of treating or preventing an infectious disease caused by Coronaviridae or a mutant thereof in a subject in need thereof, the method comprising administering to the subject a therapeutically effective amount of a compound as defined in any one of claims 1 to 17 or a composition as defined in claim 21 .

24. The method according to claim 23, wherein the infectious disease caused by Coronaviridae or a mutant thereof is a disease caused by SARS-CoV-2 or a mutant thereof.

25. The method of claim 24, wherein the recombinant lectin protein inhibits the interaction or binding of SpikeS 1 protein of SARS-CoV2 with ACE2 receptor; and inhibits or modulates the cytokine storm induced by SpikeS 1 proteins of Coronaviridae or a mutant thereof.

26. The method of claim 23, wherein said treatment or prevention comprises administering compound of Formula (I) at a dose of 0.01 to 1000 mgper kg of subject’s bodyweight. 27. Use of a compound as defined in any one of claims 1 to 17 or a composition as defined in claim 21, for the manufacture of a medicament for use in the treatment or prevention of an infectious disease caused by Coronaviridae or a mutant thereof.

28. Use according to claim 27, wherein the infectious disease caused by Coronaviridae or a mutant thereof is a disease caused by SARS-CoV-2 or a mutant thereof.