WO2016112768A1 - Benzofuroxan oxide histone deacetylase inhibitor, and preparation method therefor and uses thereof - Google Patents

Abstract

The present invention relates to a benzofuroxan oxide histone deacetylase inhibitor, and a preparation method therefor and uses thereof. The compound has a structure represented by a formula I or I', a tautomer II represented by the formula I, and a tautomer II' represented by the formula I'. The present invention further relates to a pharmaceutical composition comprising a compound with a structure represented by the formula I, I', II or II'. The compound of the present invention is used for preparing a drug for preventing or treating mammalian diseases associated with the abnormal expression of the histone deacetylase activity.

Description

Benzofuroxime histone deacetylase inhibitor and preparation method and application thereof Technical field

The invention relates to a benzofurazan histone deacetylase inhibitor, a preparation method and application thereof, and belongs to the technical field of chemistry.

Background technique

Studies have shown that the occurrence of tumors is closely related to the imbalance between acetylation and deacetylation of lysine residues at the N-terminus of nucleosome core proteins. Histone acetylation is a dynamic reversible process that is regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs). HAT transfers the acetyl group of acetyl-CoA to the specific lysine residue at the amino terminus of histones. This state facilitates the dissociation of DNA from histone octamers, and the nucleosome structure is relaxed, thereby enabling various transcriptions. Factor and synergistic transcription factors bind specifically to the DNA binding site, activating transcription of the gene; whereas HDAC is positively charged by the deacetylation of the N-terminus of histones (reaction II), and thus with negatively charged DNA In close association, chromatin is a tightly curled repressor structure that inhibits the transcriptional expression of certain genes, such as tumor suppressor genes. At present, there are 18 members of the HDACs family found in the human body, which can be divided into four categories according to their structure, function and distribution. Among them, class I (HDAC1, 2, 3 and 8), class II (IIa: HDAC 4, 5, 7 and 9; IIb: HDAC 6 and 10), class IV (HDAC11) belongs to zinc ion-dependent hydrolase, and Class III HDACs (SIR 1-7) are NAD+ dependent.

Histone deacetylase inhibitors (HDACi) can regulate apoptosis and differentiation-related protein expression and stability by inducing histone acetylation in specific regions of chromatin, and induce apoptosis and differentiation. At the same time, HDACi has the advantages of wide anti-tumor spectrum and low toxic and side effects. They have good inhibitory activity against solid tumors, leukemias and lymphomas. The metal binding region of HDACi can directly interact with the zinc ion of the active site, form hydrogen bonds with histidine and tyrosine, and the link region is just in full contact with the narrow capsule. The surface recognition region is suitable for the edge of the capsule. The residues are in close contact. Therefore, designing inhibitors for HDACs as targets has become a hot spot in anti-tumor drug research.

Nitric oxide (NO) is an important messenger molecule in the body, involved in vascular regulation, neurotransmission, inflammation and immune response, and NO can inhibit tumor development through various pathways. Although the mechanism of action of NO in tumor progression is not clear, continuous low concentrations of NO in the body can promote cell growth and inhibit apoptosis, while high concentrations NO can produce cytotoxicity, induce tumor cell apoptosis, prevent the spread and metastasis of tumor cells, and tumor cells are more sensitive to NO than normal cells. The NO donor anti-tumor drug JS-K has been included in the rapid development program by NCI. Furfuryl oxynitride (formula II), which is a NO donor, has been paid more and more attention. More and more researchers have tried to use furfuryl oxynitride as a NO donor for the design and synthesis of tumor drugs and made some progress.

HDACi also has potential application value in inflammation, neurotransmission, vascular regulation and cardiovascular disease, which coincides with the role of NO. According to the results of this study, the two should cooperate in the treatment of certain diseases. effect. In 2011, Key, H.J found that in the treatment of cardiac hypertrophy, the two did play a synergistic role; afterwards, some researchers found that the two also play a synergistic role in the treatment of wound healing.

Summary of the invention

The present invention is directed to the deficiencies of the prior art, and provides a benzofuroxime oxide histone deacetylase inhibitor having both a dual action of inhibiting deacetylase and releasing nitric oxide, and the present invention also provides preparation of the compound. Method and use.

The technical scheme of the present invention is as follows:

I. Benzofurazan oxide histone deacetylase inhibitor

A benzofuroxime oxide histone deacetylase inhibitor having the structure of Formula I or I', and the tautomer II of Formula I or the tautomer II of Formula I' ', an optical isomer, a mixture of diastereomers and racemates, a pharmaceutically acceptable salt, solvate or prodrug thereof;

among them,

X is oxygen or an amino group;

R ₁ is a saturated aliphatic chain of various C1-8, a branched saturated aliphatic chain, an olefin chain, an alkyne chain, an alkoxy chain, an aroyl group, a heteroaryl group, a cycloalkyl group, a C1-8 heteroalkyl group. An aromatic group having a substituent or a heteroaryl group having a substituent;

R ₂ is hydroxamic acid, hydroxy, carboxy, methoxycarbonyl, amido, hydrazide or N-(2-aminophenyl)amide;

R ₃ represents a hydrogen, ortho, meta, or parafluoro, chloro, bromo, iodo halogen, hydroxy, amino, methoxy, ethoxy, or cyano group.

Preferably, in the above formula I,

X is oxygen;

R ₁ is a saturated aliphatic chain of C1-8, an unsaturated aliphatic chain of C1-8, an aromatic chain of C1-9, a fatty chain containing a hetero atom of C1-8, and a heterocyclic ring of C1-9;

R ₂ is a hydroxyl group, a carboxyl group, a methoxycarbonyl group, an ethoxycarbonyl group, a hydroxamic acid;

R ₃ is hydrogen.

Further preferably, the above compound of formula I is one of the following:

5-((4-(hydroxyamino)-4-oxobutyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (5a);

5-((5-(hydroxyamino)-5-oxopentyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (5b);

5-((6-(hydroxyamino)-6-oxohexyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (5c);

5-((7-(hydroxyamino)-7-oxoheptyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (5d);

5-((8-(hydroxyamino)-8-oxooctyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (5e);

4-((4-(hydroxyamino)-4-oxobutyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (10a);

4-((5-(hydroxyamino)-5-oxopentyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (10b);

4-((6-(hydroxyamino)-6-oxohexyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (10c);

4-((7-(hydroxyamino)-7-oxoheptyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (10d);

4-((8-(hydroxyamino)-8-oxooctyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (10e);

5-((3-carboxypropoxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (4a);

5-((4-carboxybutoxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (4b);

5-((5-carboxypentyloxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (4c);

5-((6-carboxyhexyloxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (4d);

5-((7-carboxyheptyloxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (4e);

4-((3-carboxypropoxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (9a);

4-((4-carboxybutoxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (9b);

4-((5-carboxypentyloxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (9c);

4-((6-carboxyhexyloxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (9d);

4-((7-carboxyheptyloxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (9e);

5-((4-hydroxybutoxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (3a);

5-((5-hydroxypentyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (3b);

5-((6-hydroxyhexyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (3c);

5-((7-hydroxyheptyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (3d);

5-((8-hydroxyoctyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (3e);

4-((4-hydroxybutoxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (8a);

4-((5-hydroxypentyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (8b);

4-((6-hydroxyhexyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (8c);

4-((7-hydroxyheptyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (8d);

4-((8-hydroxyoctyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (8e);

5-((5-(Hydroxyamino)-4-oxopentyl)carbamoyl)benzo[c][1,2,5]oxadiazole-1-oxide (12a)

5-((5-(Hydroxyamino)-5-oxopentyl)carbamoyl)benzo[c][1,2,5]oxadiazole-1-oxide (12b)

5-((5-(Hydroxyamino)-6-oxopentyl)carbamoyl)benzo[c][1,2,5]oxadiazole-1-oxide (12c)

5-((5-(Hydroxyamino)-7-oxopentyl)carbamoyl)benzo[c][1,2,5]oxadiazole-1-oxide (12d)

5-((5-(Hydroxyamino)-8-oxopentyl)carbamoyl)benzo[c][1,2,5]oxadiazole-1-oxide (12e)

5-((5-((2-Aminophenyl)amino)-4-oxopentyl)oxy)carbonyl)benzo[c][1,2,5]oxadiazole-1-oxide ( 13a);

5-((5-((2-Aminophenyl)amino)-5-oxopentyl)oxy)carbonyl)benzo[c][1,2,5]oxadiazole-1-oxide ( 13b);

5-((5-((2-Aminophenyl)amino)-6-oxopentyl)oxy)carbonyl)benzo[c][1,2,5]oxadiazole-1-oxide ( 13c);

5-((5-((2-Aminophenyl)amino)-7-oxopentyl)oxy)carbonyl)benzo[c][1,2,5]oxadiazole-1-oxide ( 13d);

5-((5-((2-Aminophenyl)amino)-8-oxopentyl)oxy)carbonyl)benzo[c][1,2,5]oxadiazole-1-oxide ( 13e);

The terms and definitions used in the present invention have the following meanings:

"Aromatic group" means an aromatic carbocyclic group. Preferred aromatic rings contain from 6 to 10 carbon atoms.

"Heteroaryl" is an aromatic heterocyclic ring which may be a monocyclic or bicyclic group. Preferred heteroaryl groups include thienyl, furyl, pyrrolyl, pyridyl, pyrazinyl, thiazolyl, pyrimidinyl, quinolinyl, tetrazolyl, thiazolyl, benzofuranyl or fluorenyl Wait.

"Heteroalkyl" is a saturated or unsaturated chain containing carbon atoms and at least one heteroatom, wherein any one of the heteroatoms is not adjacent. The heteroalkyl group contains 2 to 15 atoms (carbon atoms), preferably 2 to 10 atoms. Heteroalkyl groups can be straight or branched Chain, substituted or unsubstituted.

"Cycloalkyl" is a substituted or unsubstituted, saturated or unsaturated cyclic group containing a carbon atom and/or one or more heteroatoms. The ring may be a single ring or a fused ring, a bridged ring or a spiro ring. The monocyclic ring usually has 3 to 9 atoms, preferably 4 to 7 atoms, and the polycyclic ring contains 7 to 17 atoms, preferably 7 to 13 atoms.

"Aroyl" means a group having a carbonyl group attached to the end of the aromatic carbocyclic ring, and a preferred aromatic ring contains 6 to 10 carbon atoms.

"Pharmaceutically acceptable salt" refers to a salt form of a compound of formula (I) which is therapeutic and non-toxic. It may have any acidic group (such as a carboxyl group) to form an anionic salt, or any basic group (such as an amino group) to form a cationic salt. Many such salts are known in the art. a cationic salt formed on any acidic group such as a carboxyl group, or an anionic salt formed on any basic group such as an amino group, many of which are known in the art, such as a cationic salt including an alkali metal Salts such as sodium and potassium and alkaline earth metals (magnesium and calcium) and organic salts (such as ammonium salts). It is also convenient to obtain an anionic salt by treating the basic form of (I) with a corresponding acid, such as an inorganic acid such as sulfuric acid, nitric acid, phosphoric acid, etc.; or an organic acid such as acetic acid, propionic acid, glycolic acid, 2-hydroxyl Propionic acid, 2-oxopropionic acid, oxalic acid, malonic acid, succinic acid, maleic acid, fumaric acid, malic acid, tartaric acid, 2-hydroxy-1,2,3-malonic acid, ethanesulfonic acid, Benzoic acid, 4-methylbenzenesulfonic acid, cyclohexylsulfinic acid, 2-hydroxybenzoic acid, 4-amino-2-hydroxybenzoic acid, and the like. In addition, the skilled artisan may take another salt depending on factors such as solubility, stability, ease of preparation, and the like. The determination and optimization of these salts is within the skill of the artisan.

A "solvate" is a complex formed by the combination of a solute (such as a metalloproteinase inhibitor) and a solvent (such as water). See J. Honig et al, The Van Nostrand Chemist's Dictionary, p. 650 (1593). The pharmaceutically acceptable solvents employed in the present invention include those which do not interfere with the biological activity of metalloproteinase inhibitors (e.g., water, ethanol, acetic acid, N,N-dimethylformamide, dimethyl sulfoxide, and techniques in the art). Solvents referred to by personnel or easily identified).

As used herein, "optical isomers", "enantiomers", "diastereomers", "racemates" and the like define all possible stereoisomeric forms of the compounds of the invention or physiological derivatives. Unless otherwise indicated, the chemical nomenclature of the compounds of the invention includes mixtures of all possible stereochemical forms, the mixtures comprising all diastereomers and enantiomers of the basic structural molecule, and the substantially pure individual isomers of the compounds of the invention. Form, i.e., other isomers containing less than 10%, preferably less than 5%, especially less than 2%, and most preferably less than 1%. The various stereoisomeric forms of the peptoid compounds of the invention are expressly included within the scope of the invention.

The compounds of formula I may also exist in other protected forms or derivatives, and such forms will be apparent to those skilled in the art and are intended to be included within the scope of the invention.

The substituent as described above may itself be substituted with one or more substituents. Such substituents include those listed in C. Hanch and A. Leo, Substituent Constants for Correlation Analysis in Chemistry and Biology (1979). Preferred substituents include, for example, alkyl, alkenyl, alkoxy, hydroxy, oxy, nitro, amino, aminoalkyl (such as aminomethyl, etc.), cyano, halogen, carboxy, carbonyl alkoxy ( Such as carbonyl ethoxy, etc., thio, aryl, cycloalkyl, heteroaryl, heterocycloalkyl (such as piperidinyl, morpholinyl, pyrrolyl, etc.), imino, hydroxyalkyl, aryl Oxylate, Arylalkyl, and combinations thereof.

In addition, according to literature information (AM Gasco, G Ermondi, R Fruttero, A Gasco. Eur. J. Med. Chem. 1996, 31,3-10; Sonja Visentin, Pascale Amiel, Roberta Fruttero, Donatella Boschi, Christian Roussel, Laura Giusta, Emilio Carbone, and Alberto Gasco. J. Med. Chem. 1999, 42, 1422-1427; Gabriela Aguirre, Luca Boiani, Mariana Boiani, Hugo Cerecetto, Rossanna Di Maio, Mercedes Gonzalez, Williams Porcal, Ana Denicola, Oscar E .Piro, Eduardo E. Castellano, Carlos Mauricio R. Sant'Anna and Eliezer J. Barreiro. Bioorg. Med. Chem. 2005, 13, 6336–6346) The presence of benzoxanthene compounds in the presence of tautomerism Such tautomerism will be apparent to those skilled in the art, and thus tautomers of the benzofuroxan compound of the present invention should also be included in the scope of the present invention.

2. Method for preparing benzofuroxime histone deacetylase inhibitor of the present invention

The preparation method of the compound is as follows:

The synthetic route is as follows:

4-Amino 3-nitrobenzoic acid is used as a raw material, and after azide nitridation, the key intermediate 2 is obtained by rearrangement reaction, followed by esterification (3a-3e), oxidation to obtain carboxylic acid compound 4a-4e, and finally The target product hydroxamic acid 5a-5e is prepared by condensation of hydroxylamine hydrochloride;

Or the synthetic route is as follows:

2-Amino 3-nitrobenzoic acid is used as a raw material, and after azide nitridation, the key intermediate 7 is obtained by rearrangement reaction, followed by esterification (8a-8e), oxidation to obtain carboxylic acid compound 9a-9e, and finally The target product hydroxamic acid 10a-10e is prepared by condensation of hydroxylamine hydrochloride;

The reagents in the above synthetic route are: (a) sodium nitrite, hydrochloric acid, sodium azide; (b) toluene; (c) C4-C8 linear primary diol, PyBOP, triethylamine; (d) Jones reagent, acetone; (e) isobutyl chloroformate, triethylamine, tetrahydrofuran; hydroxylamine hydrochloride, potassium hydroxide, methanol;

The subsequent synthetic route three is as follows:

The reagents in the above synthetic route are: (a) NH ₂ (CH ₂ ) _n COOCH ₃ , n = 3-7, PyBOP, triethylamine; (b) potassium hydroxylamine, anhydrous methanol;

The subsequent synthetic route is as follows:

The reagent in the above reaction scheme: (a) o-phenylenediamine, EDC, DMAP, triethylamine, anhydrous dichloromethane;

R ₁ and R _{3 are} as defined in the above formulas I and I'.

The structural formula of the target compound of the synthetic route is shown in Table 1 below:

Table 1 Structures of target compounds 5a-5e, 10a-10e, 12a-12e, 13a-13e

The specific procedures for the preparation of the compounds are illustrated in the examples.

Those skilled in the art can vary the above steps to increase the yield. They can determine the route of synthesis according to the basic knowledge in the art, such as selecting reactants, solvents and temperatures, and avoiding side reactions by using various conventional protecting groups. Occurs to increase the yield. These conventional methods of protection can be found, for example, in T. Greene, Protecting Groups in Organic Synthesis.

Third, the application of benzofuroxime oxide histone deacetylase inhibitor

The present invention also provides the use of the above compounds for the preparation of a medicament for preventing or treating a mammalian disease associated with abnormal expression of histone deacetylase activity. The mammalian diseases associated with abnormal expression of histone deacetylase activity include cancer, neurodegenerative diseases, viral infections, inflammation, leukemia, malaria or diabetes. Accordingly, the present invention also relates to pharmaceutical compositions containing a structural compound of formula I.

Further, the present invention also encompasses a pharmaceutical composition suitable for parenteral administration to a mammal, comprising a compound of the above formula I, and a pharmaceutically acceptable carrier, optionally comprising one or more pharmaceutically acceptable excipients Agent. Due to the high homology of the catalytic centers of the zinc ion-dependent histone deacetylases (HDACs), a mixed enzyme of histone deacetylases 1 and 2, which is known to have an X-ray diffraction crystal structure (HDAC1and 2) ) to carry out enzyme activity tests.

HDACs active fluorescence analysis method (two-step method), can quickly and easily detect HDACs activity, simple operation, high sensitivity. The first step consists of an acetylated side chain lysine HDACs fluorogenic substrate Boc-Lys(acetyl)-AMC (Boc-Lys(acetyl)-AMC), incubated with the HDAC1&2 sample containing the expression to deacetylate the substrate. Base, activate the substrate. In the second step, Boc-Lys-AMC is hydrolyzed with Trypsin to produce a fluorescent group (i.e., chromophore) of 4-amino-7-methyl-coumarin (AMC) at excitation wavelength/emission. The fluorescence intensity was measured at a wavelength (390 nm/460 nm), and the inhibition rate was calculated from the fluorescence intensity of the inhibitor group and the control group, and the IC50 value was calculated. The principle of enzyme activity test is shown in the following reaction formula IV.

The cell viability of the compound was tested by thiazolyl assay (MTT method), human leukocyte leukemia cells (HEL) and human colon cancer cells (HCT-116) cell suspension were seeded in 96-well plates, and different concentrations of compounds were added to each well. Cultivation After incubation, the cells were stained with MTT, and after incubation, the absorbance (OD value) of each well was measured at 570 nm on a microplate reader, and the cell growth inhibition rate was calculated to determine the activity of the compound.

In vitro inhibition experiments of compounds of formula I demonstrate that such compounds are a histone deacetylase inhibitor.

The furazan-type NO donor compound generally releases NO by reacting with various thiol compounds such as cysteine residues of proteins, and the strong nucleophile RS ^- ion can attack the Furoxans-type compound. The 3- or 4-position of the 2,5-oxadiazole-2-oxide heterocyclic ring is opened to form a nitroso compound intermediate, and then the elimination reaction occurs to form NO, and the generated NO can be O ₂ in the solution. Rapid oxidation to nitrite ions (NO ^2- ) and nitrate removal (NO ^3- ) (see Reaction Formula V). According to the above principle, the in vitro NO release test of the furazan-type NO donor compound is usually carried out by a method of incubation at 37 ° C in an L-cys solution.

Griess method is the classical method of measuring the concentration of NO, which is determined by the principle of NO metabolites nitrite ions (NO ^2-) Indirect content to measure the concentration of NO, nitrite ion (NO ^2-) with Griess reagent (Sulphanilamide, 0.2% N-(l-naphthyl)ethylenediamine dihydrochloride, H ₃ PO ₄ ) is subjected to diazonium-azotization to form colored azo Compound (Azo compound) (see Reaction Formula VI), which has an absorption peak in the range of 540-560 nm, can be measured by visible light spectrophotometry and its concentration is calculated. The method is simple and convenient, and is often used for measuring the in vitro release of NO.

Using the NO detection kit (Biyuntian Biotechnology Research Institute), the sample is the supernatant of the cell culture medium, the cell culture medium is DMEM + 10% FBS, and the standard is diluted with DMEM + 10% FBS, and the concentration of the standard can be taken as 0. 1,2,5,10, 20,40,60,100μM, with 540nm out of the detection absorbance A, absorbance A as the ordinate, NO ^2- concentration C as the abscissa plot to obtain the standard curve. Human colon cancer cells (HCT-116) were seeded in 24-well plates, and after incubation with the corresponding concentrations of the tested compounds, the reagents I and II in the kit were sequentially added, and the absorbance was measured at a wavelength of 540 nm ( OD), followed by a standard curve, can calculate the corresponding release of nitric oxide.

Intracellular nitric oxide release experiments of compounds of formula I demonstrate that such compounds release large amounts of nitric oxide in tumor cells.

The derivative of the benzofurazan oxide heterocycle of the present invention spatially matches the active site of the histone deacetylase, and at the same time releases a large amount of nitric oxide, thus exhibiting high inhibition in vitro. active.

IV. Pharmaceutical composition containing the compound of the present invention

Partial extensions of the invention may exist in free form or in the form of a salt. Many compound types of pharmaceutically acceptable salts and methods for their preparation are known to those skilled in the art. Pharmaceutically acceptable salts include the conventional non-toxic salts, including the bases of such compounds with quaternary ammonium salts in the form of inorganic or organic acids.

The compounds of the invention may form hydrates or solvates. Those skilled in the art are aware of hydrates formed when the compound is lyophilized with water or a method of forming a solvate when concentrated in a solution with a suitable organic solvent.

The invention includes a pharmaceutical composition comprising a therapeutic amount of a compound of the invention, and one or more pharmaceutically acceptable carriers and/or excipients. Carriers include saline, buffered saline, dextrose, water, glycerol, ethanol, and combinations thereof, as discussed in more detail below. The composition may also contain minor amounts of wetting or emulsifying agents, or pH buffering agents, if desired. The composition may be a liquid, suspension, emulsion, tablet, pill, capsule, sustained release formulation or powder. The composition can be formulated as a suppository with conventional binders and carriers such as triglycerides. Oral formulations may include standard carriers such as pharmaceutical grades of mannitol, lactose, starch, magnesium stearate, sodium saccharin, cellulose and magnesium carbonate, and the like. Depending on the formulation desired, it can be configured to mix, granulate and compress or dissolve the ingredients. In another approach, the composition can be configured as nanoparticles.

The pharmaceutical carrier used can be either solid or liquid.

Typical solid carriers include lactose, terra alba, sucrose, talc, gel, agar, pectin, acacia, magnesium stearate, stearic acid and the like. The solid carrier may include one or more substances which may act as both a flavoring agent, a lubricant, a solubilizer, a suspending agent, a filler, a glidant, a compression aid, a binder or a tablet-disintegrant; It can be an encapsulating material. In the powder, the carrier is a finely divided solid which is mixed with the finely divided active ingredient. The active ingredient in the tablet is mixed with the carrier having the necessary compression properties in a suitable ratio, compressed in the desired shape and size. The powders and tablets preferably comprise up to 99% active ingredient. Suitable solid carriers include, for example, calcium phosphate, magnesium stearate, talc, sugar, lactose, dextrin, starch, gelatin, cellulose, methylcellulose, sodium carboxymethylcellulose, polyvinylpyrrolidone, Low melting point wax and ion exchange resin.

Typical liquid carriers include syrup, peanut oil, olive oil, water, and the like. The yoke carrier is used to prepare solutions, suspensions, emulsions, syrups, elixirs and sealed compositions. The active ingredient can be dissolved or suspended in a pharmaceutically acceptable liquid carrier Such as water, organic solvents, and mixtures of these or pharmaceutically acceptable oils or fats. The liquid carrier may contain other suitable pharmaceutical additives such as solubilizers, emulsifiers, buffers, preservatives, sweeteners, flavoring agents, suspending agents, thickening agents, pigments, viscosity modifiers, stabilizing or osmotic pressure-adjusting Agent. Suitable examples of liquid carriers for oral and parenteral administration include water (partially containing additives such as those described above, such as cellulose derivatives, preferably sodium carboxymethylcellulose solution), alcohols (including monohydric and polyhydric alcohols) For example, ethylene glycol) and their derivatives, and oils (such as fractionated coconut oil and peanut oil). Carriers for parenteral administration may also be oils such as ethyl oleate and isopropyl myristate. Sterile liquid carriers are used in sterile liquid compositions for parenteral administration. The liquid carrier used in the pressurized compositions can be a halogenated hydrocarbon or other pharmaceutically acceptable propellant. Sterile or Suspension Liquid pharmaceutical compositions can be used, for example, intravenous, intramuscular, intraperitoneal or subcutaneous injection. At the time of injection, a single push or gradual infusion can be performed for 30 minutes of intravascular perfusion. The compound can also be administered orally in the form of a liquid or solid composition.

The carrier or excipient may include time delay materials which are inhibited in the art, such as glyceryl monostearate or glyceryl distearate, and may also include waxes, ethylcellulose, hydroxypropylmethylcellulose, methacrylic acid. Methyl ester, etc. When it is known to be used orally, it is recognized that 0.01% Tween 80 in PHOSALPG-50 (phospholipid and 1,2-propanediol concentrate, A. Nattermann & Cie. GmbH) is used for the formulation of acceptable oral preparations of other compounds. It can be adapted to the formulation of the various compounds of the invention.

A wide variety of pharmaceutical forms can be used in administering the compounds of the invention. If a solid carrier is used, the preparation may be in the form of a tablet, in the form of a powder or pill in a hard capsule or in the form of a lozenge or lozenge. The amount of solid carrier varies to a large extent, but is preferably from about 25 mg to about 1.0 g. If a liquid carrier is used, the preparation may be a syrup, emulsion, soft capsule, sterile injection solution or suspension in a vial or non-aqueous liquid suspension.

In order to obtain a stable water-soluble dosage form, the compound or its salt which is acceptable for learning can be an aqueous solution of an organic or inorganic acid, a 0.3 M succinic acid or citric acid solution. Alternatively, acidic derivatives may be honored with a suitable alkaline solution. If a soluble form is not available, the compound can be dissolved in a suitable cosolvent or combination thereof. Examples of such suitable co-solvents include, but are not limited to, ethanol having a concentration ranging from 0 to 60%, propylene glycol, polyethylene glycol 300, polysorbate 80, glycerin, polyoxyethylene fatty acid esters, A fatty alcohol or a glycerol hydroxy fatty acid ester or the like.

Various delivery systems are known and can be used for the administration of compounds or other various formulations including tablets, capsules, injectable solutions, capsules in liposomes, microparticles, microcapsules and the like. Non-methods of introduction include, but are not limited to, dermal, intradermal, intramuscular, intraperitoneal, intravenous, subcutaneous, intranasal, pulmonary, epidural, ocular and (usually preferred) oral routes. The compound can be administered by any convenient or other suitable route, such as by infusion or bolus injection, by epithelial or mucosal routes (eg, oral mucosa, rectal and intestinal mucosa, etc.) or by drug-loaded stents and can be used with Other bioactive agents are administered together. It can be administered systemically or locally. For the treatment or prevention of nasal, bronchial or pulmonary diseases, the preferred route of administration is oral, nasal or bronchial aerosol or nebulizer.

The compounds 5d, 9d of the present invention have a significantly high inhibitory activity against histone deacetylase (HELA cell extract). It is a positive drug and can release a large amount of nitric oxide. It has good development prospects and can be used as a lead compound for the discovery of novel high-efficiency histone deacetylase inhibitors. In addition, the compounds 5d, 9d showed some activity in the anti-tumor cell proliferation test in vitro, and it is worth further structural optimization and development.

DRAWINGS

Figure 1 is a graph showing the release amount of nitric oxide released from a target compound in HCT-116 cells. The abscissa is the name of the compound and the ordinate is the multiple of the nitrate produced by the experimental test (relative to the blank group).

Detailed ways

The present invention will be further described below in conjunction with the embodiments, but is not limited thereto.

Example 1 Synthesis of Compounds 5a-5e of the Invention

Synthesis of compound 5-benzoic acid [c][1,2,5]oxadiazole 1-oxide (2):

4-Amino-3-nitrobenzoic acid (3.6 g, 20 mmol) was placed in a reaction flask, and 100 mL of 35% (V/V) hydrochloric acid was added to stir at room temperature, and then cooled to 0-5 ° C in an ice salt bath. A 33% (m/V) aqueous solution of sodium nitrite (4.4 mL) was added, and the mixture was stirred for 1 hour in an ice bath. An aqueous solution of sodium azide (1.3 g/5 mL) was slowly added dropwise, keeping the temperature inside the bottle below 30 ° C, and after completion, stirring was continued at room temperature for 1.5 hours, and the reaction was completed. The product was filtered to give a pale yellow solid. Compound 1 was placed in a reaction flask, 100 mL of toluene was added, and the mixture was heated to reflux at 80 ° C. After about 1 hour, the reaction was completed. Filtration gave a pale yellow solid, dried and recrystallized from ethanol to afford compound 2. ^{1 H NMR (600MHz, DMSO)} δ13.80 (s, 1H), 8.21 (d, J = 182.0Hz, 1H), 7.86 (s, 2H).

Synthesis of Compound 3:

Compound 2 (0.9 g, 5 mmol), 1.2 mL of 1,4-butanediol, PyBOP (3.1 g, 6 mmol), triethylamine (1.6 mL, 6.5 mmol) were placed in a reaction flask, and 50 mL of dry dichloromethane was added. Dissolved under stirring, and the reaction was carried out by TLC. After 10 hours, the reaction was completed. The solvent was evaporated to dryness, and extracted with ethyl acetate (3×50 mL), and washed successively with distilled water and brine. The organic phase was separated, dried over anhydrous sodium sulfate EtOAc EtOAc EtOAc

Compound 5-((4-Hydroxybutoxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (3a): pale yellow solid, yield: 72%. ^{1 H NMR (600MHz, DMSO)} δ8.39-8.05 (m, 1H), 7.95-7.69 (m, 2H), 4.35 (t, J = 6.6Hz, 2H), 3.47 (t, J = 6.4Hz, 2H ), 1.82 - 1.76 (m, 2H), 1.58 (dt, J = 13.4, 6.5 Hz, 2H). ¹³ C NMR (125 MHz, DMSO) δ 166.04, 159.91, 139.85, 132.44, 131.39, 121.71, 66.74, 62.37, 30.25 , 27.37. MS: [M+H ⁺ ]: Found m/z 253.2 Calcd m/z 252.2.

Compound 5-((5-Hydroxypentyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (3b): pale yellow solid, yield: 66%. _{^{1 H NMR (600MHz, CDCl 3}} ) δ7.77 (dd, J = 294.4,137.8Hz, 3H), 4.36 (t, J = 6.6Hz, 2H), 3.67 (t, J = 6.4Hz, 2H), 1.81 (dd, J = 14.8, 7.1 Hz, 2H), 1.67 - 1.59 (m, 2H), 1.56 - 1.47 (m, 2H). ¹³ C NMR (151 MHz, CDCl ₃ ) δ 171.24, 164.11, 66.28, 62.62, 32.34, 28.55, 22.44. MS: [M+H ⁺ ]: Found m/z 267.3 Calcd m/z 266.3.

Compound 5-((6-Hydroxyhexyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (3c): pale yellow solid, yield: 68%. ^{1 H NMR (600MHz, DMSO)} δ7.88 (m, 3H), 4.32 (t, J = 6.3Hz, 2H), 3.40 (dd, J = 11.2,6.2Hz, 2H), 1.77-1.71 (m, 2H ), 1.47–1.38 (m, 4H), 1.39–1.33 (m, 2H). ¹³ C NMR (131 MHz, DMSO) δ 166.04, 159.91, 139.85, 132.44, 131.39, 121.71, 66.74, 62.37, 33.01, 29.32, 26.58, 26.25. MS: [M ⁺ H ⁺ ]: Found m/z 281.3 Calcd m/z 280.3.

Compound 5-((7-Hydroxyheptyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (3d): mp. _{^{1 H NMR (600MHz, CDCl 3}} ) δ8.19 (s, 1H), 7.83 (s, 1H), 7.54 (s, 1H), 4.35 (t, J = 6.7Hz, 2H), 3.63 (t, J = 6.6 Hz, 2H), 1.81 - 1.75 (m, 2H), 1.56 (dd, J = 13.5, 6.7 Hz, 2H), 1.45 (dt, J = 14.4, 7.2 Hz, 2H), 1.41 - 1.36 (m, 4H) ¹³ C NMR (151 MHz, CDCl ₃ ) δ 163.96, 130.63, 120.20, 116.65, 66.27, 62.80, 32.62, 28.97, 28.50, 25.90, 25.61. MS: [M+H ⁺ ]:Found m/z 295.3Calcd m/ Z294.3.

Compound 5-((8-Hydroxyoctyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (3e): pale yellow solid, yield: 54%. _{^{1 H NMR (600MHz, CDCl 3}} ) δ8.01 (s, 1H), 7.67 (s, 1H), 7.38 (s, 1H), 4.43 (t, J = 6.5Hz, 2H), 3.71 (t, J = 6.4 Hz, 2H), 1.84 - 1.70 (m, 2H), 1.61 (dd, J = 13.2, 6.6 Hz, 2H), 1.42 - 1.37 (m, 2H), 1.31 (dd, J = 17.1, 8.1 Hz, 4H) ¹³ C NMR (151 MHz, CDCl ₃ ) δ 164.18, 145.32, 134.94, 133.48, 128.09, 127.92, 125.62, 66.50, 62.85, 32.68, 29.20, 29.10, 28.52, 25.81, 25.62. MS: [M+H ⁺ ]: Found m/z 30.3Calcd m/z 308.3.

Synthesis of Compound 4: (taking Compound 4a as an example)

Compound 3a (660 mg, 2.1 mmol) was placed in a reaction flask, and 10 mL of acetone was added to dissolve at room temperature with stirring, and 1.1 mL of Jones reagent was added dropwise under ice bath. After the addition was completed, stirring was continued at room temperature, and the reaction was carried out by TLC. After about 5 hours, the reaction was completed, the resulting green precipitate was filtered, and the solvent was evaporated to ethyl ether (3×50 mL), and the mixture was washed with distilled water and brine. The organic phase was separated, dried over anhydrous sodium sulfate (EtOAc)

Compound 5-((3-Carboxypropyloxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (4a): pale yellow solid, yield: 56%. ^{1 H NMR (600MHz, DMSO)} δ12.16 (s, 1H), 8.31 (d, J = 183.7Hz, 1H), 7.98-7.68 (m, 2H), 4.34 (t, J = 6.3Hz, 2H), 2.43 (t, J = 7.2 Hz, 2H), 2.01 - 1.95 (m, 2H). ¹³ C NMR (151MHz, DMSO) δ 177.25, 166.04, 159.91, 139.85, 132.44, 131.39, 121.71, 65.66, 31.84, 24.36.MS :[M+H ⁺ ]:Found m/z 267.2Calcd m/z 266.2.

Compound 5-((4-carboxybutoxy)carbonyl)benzo[c][5]oxadiazol-1-oxide (4b): pale yellow solid, yield: 67%. ^{1 H NMR (600MHz, DMSO)} δ12.06 (s, 1H), 8.58-7.50 (m, 3H), 4.33 (t, J = 6.2Hz, 2H), 2.30 (t, J = 7.3Hz, 2H), 1.79–1.70 (m, 2H), 1.65 (dt, J = 14.3, 7.3 Hz, 2H). ¹³ C NMR (151 MHz, DMSO) δ 174.68, 164.22, 65.95, 33.63, 27.99, 21.53.

Compound 5-((5-carboxypentyloxy)carbonyl)benzo[c][5]oxadiazol-1-oxide (4c): pale yellow solid, yield: 72%. ^{1 H NMR (600MHz, DMSO)} δ11.98 (s, 1H), 8.51-7.56 (m, 3H), 4.32 (t, J = 6.5Hz, 2H), 2.24 (t, J = 7.3Hz, 2H), 1.74 (dd, J = 14.6, 6.9 Hz, 2H), 1.57 (dd, J = 15.1, 7.5 Hz, 2H), 1.44 (dd, J = 15.3, 8.0 Hz, 2H). ¹³ C NMR (151 MHz, DMSO) δ 174.37, 159.24, 76.02, 61.41, 29.02, 23.87, 23.63, 20.90, 19.73. MS: [M+H ⁺ ]: Found m/z 295.3Calcd m/z 294.3.

Compound 5-((6-carboxyhexyloxy)carbonyl)benzo[c][5]oxadiazol-1-oxide (4d): pale yellow solid, yield: 61%. ^{1 H NMR (600MHz, DMSO)} δ10.55 (s, 1H), 8.33-7.50 (m, 3H), 4.36 (t, J = 6.6Hz, 2H), 2.37 (t, J = 7.4Hz, 2H), 1.83–1.75 (m, 2H), 1.71–1.64 (m, 2H), 1.48–1.39 (m, 4H). ¹³ C NMR (151 MHz, DMSO) δ 174.37, 159.24, 76.02, 61.41, 29.02, 23.87, 23.63, 20.90 , 19.73. MS: [M+H ⁺ ]: Found m/z 309.3 Calcd m/z 308.3.

Compound 5-((7-carboxyheptyloxy)carbonyl)benzo[c][5]oxadiazol-1-oxide (4e): mp. _{^{1 H NMR (600MHz, CDCl 3}} ) δ11.58 (s, 1H), 7.78 (m, 3H), 4.35 (t, J = 6.5Hz, 2H), 2.35 (t, J = 7.4Hz, 2H), 1.88 -1.74 (m, 2H), 1.70 - 1.59 (m, 2H), 1.41 (dd, J = 32.3, 5.2 Hz, 6H). ¹³ C NMR (151 MHz, CDCl ₃ ) δ 180.08, 164.11, 66.37, 34.05, 28.95, 28.92, 28.60, 25.85, 24.61. MS: [M+H ⁺ ]: Found m/z 323.3 Calcd m/z 322.3.

Synthesis of Compound 5: (taking Compound 5a as an example)

4a (550 mg, 1.54 mmol) was placed in a reaction flask, and mL of dry tetrahydrofuran was added thereto, and the mixture was stirred and dissolved at room temperature. Then, isobutyl chloroformate (0.3 mL, 1.85 mmol) was added dropwise thereto in an ice bath, and the mixture was stirred and stirred in an ice bath. After the dropwise addition, triethylamine (0.55 mL, 3.08 mmol) was added dropwise, and the mixture was further stirred at room temperature for 1 hour, and then the formed precipitate was removed by filtration, and filtrate A was taken. Potassium hydroxide (129 mg, 2.3 mmol) and hydroxylamine hydrochloride (160 mg, 2.3 mmol) were placed in a reaction flask, and the dried methanol was sufficiently dissolved, and the insoluble solid was filtered off to obtain a filtrate B. The filtrate A was dropped into the filtrate B, and the reaction was further stirred at room temperature, and the progress of the reaction was examined by TLC. After 4 hours, the reaction was completed, and the mixture was adjusted to pH 3.0 with 2N hydrochloric acid, and the solvent was evaporated to ethyl ether (3×50 mL), and then washed with distilled water and brine. The organic phase was separated, dried over anhydrous sodium sulfate (EtOAc)

Compound 5-((4-(Hydroxyamino)-4-oxobutyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (5a): light yellow solid, yield: 60% . ^{1 H NMR (600MHz, DMSO)} δ10.46 (s, 1H), 8.74 (s, 1H), 8.54-8.05 (m, 1H), 8.02-7.50 (m, 2H), 4.31 (t, J = 5.6Hz , 2H), 2.15 (t, J = 6.9 Hz, 2H), 2.04 - 1.92 (m, 2H). ¹³ C NMR (151MHz, DMSO) δ 168.98, 164.23, 131.55, 118.94, 117.37, 65.73, 29.36, 24.65.HRMS :[M+Na ⁺ ]:Found m/z 304.0535Calcd m/z281.0648

Compound 5-((5-(Hydroxyamino)-5-oxopentyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (5b): light yellow solid, yield: 65% . ¹ H NMR (600 MHz, d ₆ -DMSO) δ 10.40 (s, 1H), 8.71 (d, J = 5.1 Hz, 2H), 8.18 (d, J = 9.4 Hz, 1H), 7.97 (d, J = 9.4 Hz, 1H), 4.34 (t, J = 6.2 Hz, 2H), 2.03 (d, J = 7.4 Hz, 2H), 1.74 - 1.70 (m, 2H), 1.66 (dd, J = 14.7, 7.4 Hz, 2H). ¹³ C NMR (151MHz, d _{6 -} DMSO) δ 168.85, 164.12, 149.36, 148.83, 133.67, 130.98, 119.82, 117.01, 65.48, 65.44, 31.78, 27.57, 21.65. HRMS: [M+Na ⁺ ]:Found m/z 318.0935Calcd m/z 295.0804.

Compound 5-((6-(Hydroxyamino)-6-oxohexyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (5c): pale yellow solid, yield: 68%. _{^{1 H NMR (600MHz, d 6}} -DMSO) δ10.33 (s, 1H), 8.64 (s, 1H), 7.98 (m, 3H), 4.32 (t, J = 6.5Hz, 2H), 1.99 (dd, J = 9.6, 5.1 Hz, 2H), 1.78 - 1.70 (m, 2H), 1.60 - 1.53 (m, 2H), 1.39 (dt, J = 15.0, 7.7 Hz, 2H). ¹³ C NMR (151 MHz, CDCl ₃ ) δ 170.09,166.04,159.91,139.85,132.44,131.39,121.71,66.74,34.40,29.32,25.95,23.21.HRMS:[M+Na ⁺ ]:Found m/z332.0848Calcd m/z 309.0961.

Compound 5-((7-(Hydroxyamino)-7-oxoheptyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (5d): light yellow solid, yield: 71% . _{^{1 H NMR (600MHz, d 6}} -DMSO) δ10.34 (s, 1H), 8.66 (s, 1H), 8.51-7.60 (m, 3H), 4.31 (t, J = 6.5Hz, 2H), 1.96 ( t, J = 7.3 Hz, 2H), 1.75 - 1.70 (m, 2H), 1.55 - 1.49 (m, 2H), 1.40 (dd, J = 14.8, 7.5 Hz, 2H), 1.30 (dt, J = 14.8, 7.5 Hz, 2H). ¹³ C NMR (151 MHz, d ₆ -DMSO) δ 169.55, 164.23, 131.44, 117.46, 66.23, 40.42, 40.28, 40.14, 40.00, 39.86, 39.72, 39.58, 32.66, 28.69, 28.35, 25.58, 25.45 .HRMS: [M+Na ⁺ ]: Found m/z 346.1028Calcd m/z 323.1117.

Compound 5-((8-(Hydroxyamino)-8-oxooctyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (5e): pale yellow solid, yield: 58% . _{^{1 H NMR (600MHz, d 6}} -DMSO) δ10.33 (s, 1H), 8.66 (s, 1H), 8.49-7.56 (m, 3H), 4.30 (t, J = 6.4Hz, 2H), 1.98- 1.89 (m, 2H), 1.76–1.67 (m, 2H), 1.52–1.44 (m, 2H), 1.38 (dt, J = 14.6, 7.2 Hz, 2H), 1.34–1.28 (m, 2H), 1.25 ( Dt, J = 13.7, 6.9 Hz, 2H). ¹³ C NMR (151 MHz, d _{6 -} DMSO) δ 169.12, 163.72, 65.79, 32.24, 28.48, 28.38, 27.97, 25.30, 25.06. HRMS: [M+Na ⁺ ]: Found m/z 360.1194Calcd m/z 337.1274.

The synthesis of compound 7 is carried out in the same manner as the synthesis of compound 2. ^{1 H NMR (600MHz, DMSO)} δ8.13 (ddd, J = 11.6, 8.0,1.4Hz, 2H), 7.53 (t, J = 8.0Hz, 1H). 13 C NMR (151MHz, DMSO) δ165.42,144.68, 134.82, 132.05, 127.84, 127.73, 126.24.

The synthesis of compound 8 is carried out in the same manner as the synthesis of compound 3.

Compound 4-((4-Hydroxybutoxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (8a): mp. _{^{1 H NMR (600MHz, CDCl 3}} ) δ8.07 (d, J = 7.7Hz, 1H), 7.95 (d, J = 8.1Hz, 1H), 7.38 (t, J = 7.9Hz, 1H), 4.46 (t , J = 6.6 Hz, 2H), 3.74 (t, J = 6.3 Hz, 2H), 1.92 (dt, J = 14.3, 7.1 Hz, 2H), 1.73 (dd, J = 14.0, 7.0 Hz, 2H). ¹³ C NMR (151 MHz, CDCl ₃ ) δ 134.92, 128.00, 125.59, 66.21, 62.23, 29.05, 25.18. MS: [M+H ⁺ ]: Found m/z 253.2 Calcd m/z 252.2.

Compound 4-((5-Hydroxypentyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (8b): mp. _{^{1 H NMR (600MHz, CDCl 3}} ) δ8.05 (dd, J = 7.8,1.1Hz, 1H), 7.93 (dd, J = 8.1,1.0Hz, 1H), 7.37 (t, J = 8.0Hz, 1H) , 4.40 (t, J = 6.7 Hz, 2H), 3.64 (t, J = 6.5 Hz, 2H), 1.84 - 1.77 (m, 2H), 1.60 - 1.57 (m, 2H), 1.47 - 1.44 (m, 2H) ¹³ C NMR (151MHz, CDCl ₃ ) δ 164.18, 145.32, 134.95, 133.50, 128.07, 127.94, 125.63, 66.38, 62.67, 32.52, 28.53, 25.72, 25.38. MS: [M+H ⁺ ]:Found m/z267 .3Calcd m/z 266.3.

Compound 4-((6-Hydroxyhexyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (8c): pale yellow solid, yield: 60%. _{^{1 H NMR (600MHz, CDCl 3}} ) δ8.05 (dd, J = 7.9,1.6Hz, 1H), 7.92 (dd, J = 8.1,1.6Hz, 1H), 7.37 (t, J = 8.0Hz, 1H) , 4.40 (t, J = 6.7 Hz, 2H), 3.66 (t, J = 6.4 Hz, 2H), 1.86 - 1.79 (m, 2H), 1.63 (dt, J = 14.6, 6.7 Hz, 2H), 1.52 ( Tt, J = 9.6, 6.1 Hz, 2H). ¹³ C NMR (151 MHz, CDCl3) δ 164.18, 145.26, 134.98, 133.44, 127.98, 127.96, 125.68, 117.14, 110.89, 66.32, 62.45, 32.09, 28.34, 22.22. [M+H ⁺ ]: Found m/z 281.3Calcd m/z 280.3.

Compound 4-((7-Hydroxyheptyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (8d): mp. _{^{1 H NMR (600MHz, CDCl 3}} ) δ8.04 (dd, J = 7.9,1.4Hz, 1H), 7.91 (dd, J = 8.1,1.4Hz, 1H), 7.36 (t, J = 8.0Hz, 1H) , 4.37 (t, J = 6.7 Hz, 2H), 3.60 (t, J = 6.6 Hz, 2H), 1.77 (dd, J = 14.7, 6.9 Hz, 2H), 1.54 (p, J = 6.8 Hz, 2H) , 1.42 (dd, J = 14.6, 6.9 Hz, 2H), 1.37 (dd, J = 11.5, 8.0 Hz, 4H). ¹³ C NMR (151 MHz, CDCl ₃ ) δ 164.21, 145.24, 135.04, 133.49, 128.02, 125.68, 66.49, 62.77, 32.59, 28.97, 28.47, 25.87, 25.61. MS: [M+H ⁺ ]: Found m/z 295.3 Calcd m/z 294.3.

Compound 4-((8-Hydroxyoctyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (8e): mp. _{^{1 H NMR (600MHz, CDCl 3}} ) δ8.07 (dd, J = 7.9,1.6Hz, 1H), 7.94 (dd, J = 8.1,1.5Hz, 1H), 7.38 (t, J = 8.0Hz, 1H) , 4.40 (t, J = 6.7 Hz, 2H), 3.63 (t, J = 6.6 Hz, 2H), 1.84 - 1.76 (m, 2H), 1.56 (dd, J = 13.8, 6.8 Hz, 2H), 1.48 - 1.42 (m, 2H), 1.39 (dd, J = 16.8, 8.3 Hz, 4H). ¹³ C NMR (151MHz, CDCl ₃ ) δ 164.18, 145.32, 134.94, 133.48, 128.09, 127.92, 125.62, 66.50, 62.85, 32.68, 29.20, 29.10, 28.52, 25.81, 25.62. MS: [M+H ⁺ ]: Found m/z 30.3 Calcd m/z 308.3.

The synthesis of compound 9 is carried out in the same manner as the synthesis of compound 4.

Compound 4-((3-Carboxypropyloxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (9a): mp. ^{1 H NMR (600MHz, DMSO)} δ8.07 (d, J = 7.7Hz, 1H), 7.95 (d, J = 7.9Hz, 1H), 7.38 (t, J = 7.8Hz, 1H), 4.46 (d, J = 5.9 Hz, 2H), 2.55 (t, J = 6.5 Hz, 2H), 2.23 - 2.08 (m, 2H). ¹³ C NMR (151 MHz, DMSO) δ 173.65, 159.25, 130.30, 128.94, 123.48, 122.81, 120.91 , 60.47, 25.72, 18.92. MS: [M+H ⁺ ]: Found m/z 267.2 Calcd m/z 266.2.

Compound 4-((4-carboxybutoxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (9b): mp. _{^{1 H NMR (600MHz, CDCl 3}} ) δ8.06 (d, J = 7.7Hz, 1H), 7.94 (d, J = 8.0Hz, 1H), 7.38 (t, J = 7.9Hz, 1H), 4.40 (t , J = 6.2 Hz, 2H), 2.39 (t, J = 7.1 Hz, 2H), 1.82 (dd, J = 13.3, 6.6 Hz, 2H), 1.75 - 1.66 (m, 2H), 1.55 - 1.45 (m, 2H). ¹³ C NMR (151MHz, CDCl ₃ ) δ 179.70, 164.28, 145.35, 135.18, 128.20, 125.78, 66.22, 33.86, 28.32, 25.48, 24.28. MS: [M+H ⁺ ]:Found m/z 281.2Calcd m /z 280.2.

Compound 4-((5-carboxypentyloxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (9c): mp. H NMR (600MHz, CDCl ₃ ) δ 8.04 (d, J = 10.0 Hz, 1H), 7.70 (d, J = 9.9 Hz, 1H), 7.42 (t, J = 9.0 Hz, 1H), 4.33 (t, J = 9.5 Hz, 2H), 2.21 (t, J = 16.1 Hz, 2H), 1.95 - 1.71 (m, 2H), 1.68 - 1.44 (m, 2H), 1.33 (m, 2H). ¹³ C NMR (151 MHz) , CDCl ₃ ) δ 177.25, 167.21, 166.47, 133.37, 130.99, 130.33, 116.36, 66.74, 34.54, 29.32, 25.95, 24.89. MS: [M+H ⁺ ]: Found m/z 295.3Calcd m/z 294.3.

Compound 4-((6-carboxyhexyloxy)carbonyl)benzo[c][5]oxadiazol-1-oxide (9d): mp. ¹ H NMR (600MHz, CDCl ₃ ) δ 11.18 (s, 1H), 8.07 (d, J = 7.8 Hz, 1H), 7.94 (d, J = 7.9 Hz, 1H), 7.38 (t, J = 7.9 Hz) , 1H), 4.40 (t, J = 6.4 Hz, 2H), 2.37 (t, J = 7.2 Hz, 2H), 2.08 - 1.80 (m, 2H), 1.76 - 1.62 (m, 2H), 1.58 - 1.32 ( m,4H). ¹³ C NMR (151MHz, CDCl ₃ ) δ 179.36, 164.20, 145.31, 135.02, 133.58, 128.04, 125.64, 66.35, 33.78, 28.60, 28.37, 25.61, 24.47. MS: [M+H ⁺ ]:Found m/z 309.3Calcd m/z 308.3.

The compound 4-((7-carboxyheptyloxy)carbonyl)benzo[c][5]oxadiazol-1-oxide (9e): mp. ¹ H NMR (600 MHz, CDCl ₃ ) δ 11.01 (s, 1H), 8.08 (dd, J = 7.8, 1.5 Hz, 1H), 7.95 (dd, J = 8.1, 1.5 Hz, 1H), 7.39 (t, J = 8.0 Hz, 1H), 4.41 (t, J = 6.7 Hz, 2H), 2.37 (t, J = 7.4 Hz, 2H), 1.85 - 1.79 (m, 2H), 1.70 - 1.63 (m, 2H), 1.47 (dd, J = 14.1, 6.6 Hz, 2H), 1.41 (dd, J = 12.0, 8.3 Hz, 4H). ¹³ C NMR (151 MHz, CDCl ₃ ) δ 179.69, 164.18, 134.94, 133.52, 128.08, 127.94, 125.61 , 66.42, 33.89, 28.81, 28.75, 28.47, 25.68, 24.49.

The synthesis of compound 10 is carried out in the same manner as the synthesis of compound 5.

Compound 4-((4-(Hydroxyamino)-4-oxobutyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (10a): pale yellow solid, yield: 62% . ^{1 H NMR (600MHz, DMSO)} δ10.46 (s, 1H), 8.77 (s, 1H), 8.19 (d, J = 8.0Hz, 1H), 8.14 (d, J = 7.8Hz, 1H), 7.56 ( t, J = 7.9 Hz, 1H), 4.33 (t, J = 6.1 Hz, 2H), 2.14 (t, J = 7.0 Hz, 2H), 2.00 - 1.94 (m, 2H). ¹³ C NMR (151 MHz, DMSO) ) δ 168.90, 164.26, 145.09, 135.41, 132.64, 128.72, 126.86, 65.84, 29.22, 24.65. HRMS: [M+Na ⁺ ]: Found m/z 304.0563Calcd m/z281.0648.

Compound 4-((5-(Hydroxyamino)-5-oxopentyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (10b): pale yellow solid, yield: 78% . ^{1 H NMR (600MHz, DMSO)} δ10.40 (s, 1H), 8.71 (s, 1H), 8.12 (d, J = 8.2Hz, 1H), 8.08 (d, J = 8.1Hz, 1H), 7.48 ( t, J = 7.4 Hz, 1H), 4.32 (t, J = 9.9 Hz, 2H), 2.14 (t, J = 16.1 Hz, 2H), 2.00 - 1.84 (m, 2H), 1.58 - 1.29 (m, 2H) ¹³ C NMR (151 MHz, DMSO) δ 168.79, 164.24, 145.12, 135.44, 132.54, 128.82, 126.86, 65.33, 34.40, 28.81, 23.13. HRMS: [M+Na ⁺ ]:Found m/z 318.0921Calcd m/z 295.0804.

Compound 4-((6-(Hydroxyamino)-6-oxohexyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (10c): mp. ^{1 H NMR (500MHz, Chloroform)} δ10.42 (s, 1H), 8.66 (s, 1H), 8.15 (d, J = 8.0Hz, 1H), 8.01 (d, J = 7.7Hz, 1H), 7.41 ( t, J = 7.1 Hz, 1H), 4.33 (t, J = 9.7 Hz, 2H), 2.14 (t, J = 11.2 Hz, 2H), 1.78 (tt, J = 14.2, 9.7 Hz, 2H), 1.58 - 1.22(m,4H). ¹³ C NMR (151MHz, DMSO) δ 167.79, 164.33, 145.32, 134.24, 131.21, 128.06, 125.76, 66.4334.40, 29.32, 25.95, 25.21.HRMS:[M+Na ⁺ ]:Found m /z 332.0856Calcd m/z 309.0961.

Compound 4-((7-(Hydroxyamino)-7-oxoheptyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (10d): light yellow solid, yield: 66% . _{^{1 H NMR (600MHz, d 6}} -DMSO) δ10.33 (s, 1H), 8.65 (s, 1H), 8.20 (d, J = 7.8Hz, 1H), 8.12 (d, J = 7.3Hz, 1H) , 7.57 (t, J = 8.0 Hz, 1H), 4.34 (t, J = 6.5 Hz, 2H), 1.95 (t, J = 7.3 Hz, 2H), 1.78 - 1.68 (m, 2H), 1.55 - 1.48 ( m, 2H), 1.40 (dt, J = 14.8, 7.5 Hz, 2H), 1.30 (dt, J = 14.6, 7.4 Hz, 2H). ¹³ C NMR (151 MHz, d ₆ -DMSO) δ 169.55, 164.39, 145.11, 135.26, 132.60, 128.70, 127.44, 126.94, 66.35, 32.66, 28.68, 28.37, 25.56, 25.45. HRMS: [M+Na ⁺ ]: Found m/z 346.1040Calcd m/z 323.1117.

Compound 4-((8-(Hydroxyamino)-8-oxooctyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (10e): pale yellow solid, yield: 68% . _{^{1 H NMR (600MHz, d 6}} -DMSO) δ10.30 (s, 1H), 8.61 (s, 1H), 8.20 (dd, J = 8.1,1.4Hz, 1H), 8.12 (dd, J = 7.8,1.4 Hz, 1H), 7.57 (t, J = 8.0 Hz, 1H), 4.35 (t, J = 6.6 Hz, 2H), 1.94 (t, J = 7.3 Hz, 2H), 1.76 - 1.71 (m, 2H), 1.49 (dd, J = 14.7, 7.3 Hz, 2H), 1.43 - 1.37 (m, 2H), 1.34 - 1.30 (m, 2H), 1.26 (dt, J = 13.5, 6.8 Hz, 2H). ¹³ C NMR ( 151 MHz, d ₆ -DMSO) δ 169.59, 164.39, 145.13, 135.23, 132.58, 128.68, 126.97, 66.39, 32.71, 28.92, 28.79, 28.44, 25.72, 25.49. HRMS: [M+Na ⁺ ]:Found m/z 360.3301Calcd m/z 337.1274.

Synthesis of Compound 11: (taking Compound 11b as an example)

Compound 2 (0.9 g, 5 mmol), 5-aminopentanoic acid methyl ester hydrochloride (0.92 g, 5.5 mmol), PyBOP (3.1 g, 6 mmol), triethylamine (1.6 mL, 6.5 mmol) was placed in a reaction flask Add 50 mL of dry dichloromethane to dissolve at room temperature with stirring, and the reaction was carried out by TLC. After 8 hours, the reaction was completed. The solvent was evaporated to dryness, and extracted with ethyl acetate (3×50 mL), and washed successively with distilled water and brine. The organic phase was separated, dried over anhydrous sodium sulfate (EtOAc) Yield: 62%, MS: [M+H ⁺ ]: Found m/z 294.3 Calcd m/z 294.1.

Synthesis of Compound 12: (taking Compound 12b as an example)

Preparation of potassium hydroxyamine (NH ₂ OK) solution: 14 mL of saturated potassium hydroxide solution of potassium hydroxide was added dropwise to 24 mL of anhydrous methanol solution containing 4.67 g (67 mmol) of hydroxylamine hydrochloride, and the internal temperature was controlled below 40 ° C. After completion, the reaction solution was cooled, and a white potassium chloride precipitate was filtered off, and the obtained filtrate was sealed and stored.

After compound 11b (0.59 g, 2.0 mmol) was dissolved in 10 mL of anhydrous methanol, 3.5 mL of the above-mentioned potassium hydroxyamine (NH ₂ OK) solution was added thereto. After 1 hour, the methanol was distilled off, and the solution was acidified to pH 3-4 with 2 mol/L hydrochloric acid, and then extracted with ethyl acetate. The ethyl acetate layer was combined, washed with brine, dried over anhydrous magnesium sulfate The crude product was purified by column chromatography eluting with EtOAc (EtOAc:EtOAc)

Compound 5-((5-(Hydroxyamino)-5-oxopentyl)carbamoyl)benzo[c][1,2,5]oxadiazole-1-oxide (12b): light yellow solid , Yield: 26%; HRMS (AP-ESI) m/z calcd for C ₁₁ H ₁₅ N ₄ O ₅ [M+H] ⁺ 295.1042, found 295.1055.

Synthesis of Compound 13: (taking Compound 13b as an example)

Compound 4b (0.78g, 2.8mmol), TEA (0.6mL, 3.65mmol), EDC (700mg, 3.65mmol), DMAP (412mg, 3.37mmol) was placed in a reaction flask, 10mL dry DCM was added and stirred at room temperature After 1 h, o-phenylenediamine (324.4 mg, 3.0 mmol) was added and allowed to react at room temperature overnight. The reaction was completed by TLC. After the reaction was completed, DCM was evaporated, and then diluted with ethyl acetate (3×50 mL), and the mixture was diluted and evaporated, and then washed three times with distilled water and brine, and the organic phases were combined and dried over anhydrous sodium sulfate. After drying, anhydrous sodium sulfate was filtered off, and the solvent was evaporated to give a crude material.

Compound 5-(((5-((2-aminophenyl)amino)-5-oxopentyl)oxy)carbonyl)benzo[c][1,2,5]oxadiazole-1-oxide (13b): pale yellow solid, yield: 27%; HRMS (AP-ESI) m/z calcd for C ₁₈ H ₁₉ N ₄ O ₅ [M+H] ⁺ 371.1355, found 371.1369.

Example 2. Compound 5a-5e, 10a-10e inhibits histone deacetylase activity assay (In vitro)

The enzyme activity experiment was carried out by HDACs active fluorescence analysis method, which was mainly divided into two steps: (1) lysine HDACs fluorescent substrate containing one acetylated side chain (Boc-Lys(acetyl)-AMC), containing HDAC8 containing expression The sample is incubated to deacetylate the substrate and activate the substrate. (2) Hydrolyzing a lysine HDACs fluorogenic substrate (Boc-Lys-AMC) containing an acetylated side face with trypsin to generate a fluorescent group of AMC, and measuring fluorescence at an excitation wavelength/emission wavelength (390 nm/460 nm) The intensity was calculated from the fluorescence intensity of the inhibitor group and the control group, and the IC50 value was calculated. The principle of enzyme activity test is shown in the above reaction formula IV and related content. The experimental results are shown in Table 2 (Results of in vitro inhibitory enzyme activity of Compounds 5a-5e, 10a-10e).

Table 2 Experimental results of in vitro inhibitory enzyme activities of compounds 5a-5e, 10a-10e, 12b and 13b

The values in table a are the mean ± standard deviation of three trials.

SAHA trade name Zolinza, commonly known as Vorinostat, is a histone deacetylase inhibitor approved by the US Food and Drug Administration (FDA) in 2006.

The above test results show that the compounds inhibiting cell proliferation of benzofuroxan derivative compounds have strong inhibitory activity against histone deacetylase, which has good development prospects and can be used as a novel high-efficiency histone. A lead compound for a deacetylase inhibitor.

Example 3. Activity of target compound to inhibit cell proliferation in vitro (In vitro)

The compounds in Table 1 above were selected to inhibit the proliferation of cancer cells in vitro. The results are shown in Table 3.

Explanation of terms:

HEL: human red leukocyte leukemia cells

HCT-116: Human colorectal cancer cells

Hela: cervical cancer cells

U937: Histiocytic lymphoma cells

ES-2: Human ovarian clear cell carcinoma

KG1: leukemia cell line

B16: Melanoma cells

PC-3: prostate cancer cells

SAHA: The trade name Zolinza, commonly known as Vorinostat, is a histone deacetylase inhibitor approved by the US Food and Drug Administration (FDA) in 2006.

DMSO: dimethyl sulfoxide

IC50: half inhibition concentration

1. [Materials] HEL, HCT-116, Hela, U937, ES-2, KG1, B16, PC-3 cell line, tetramethylazozolium blue MTT, 10% fetal bovine serum, 96-well plate.

2. [Method]

Cell culture The above tumor cell lines were all cultured in a conventional manner. Logarithmic growth phase cells were used in the experiments.

Cell growth assay (MTT method) The above cells were adjusted to 1 × 105 / mL, and seeded in 96-well plates (100 μL / well), 5000 cells / well. After plating for 24 hours, 100 μL of medium containing different concentrations of compound was added to each well to make the final concentration of the compound in the wells 100, 20, 4, 0.8, 0.16 μM, respectively, with three replicate wells per concentration, without cells. Hole reading Do blank, add cells without compound holes to make compound blank wells, SAHA as a compound positive control. Incubate for 48 hours at 37 ° C, 5% carbon dioxide, add 20 μL of 0.5% MTT staining solution to each well, and continue to incubate for 4 hours, discard the medium in the plate, and add dimethyl sulfoxide 20050 μL/well. The absorbance value of each well was measured at a wavelength of 490,630 nm on a microplate reader, and the cell growth inhibition rate was calculated by the following formula:

Table 3 results of inhibition of cell proliferation experiments

^a standard value is the mean ± standard deviation of three trials

The above table test data showed that the compounds 19d, 24d showed some activity in the anti-tumor cell proliferation test in vitro, and it is worthy of further testing for the release of nitric oxide.

Example 4. Target compound nitric oxide release test (In vitro)

Refer to the NO test kit (Biyuntian Biotechnology Research Institute) for a standard curve.

HCT-116 cells were selected to adjust to 1 × 10 ⁵ /mL, and seeded in 24-well plates (2 mL/well) at 50 × 10 ⁴ cells/well. 2 μL of medium containing 100 mM of compound was added to each well, and the final concentration of the compound in the well was set to three replicate wells per compound, and 2 μL of dimethyl sulfoxide SAHA was added as a positive control for the blank well. Incubate for 3 or 5 hours at 37 ° C in 5% carbon dioxide. The medium of three replicate wells was collected, centrifuged at 1200 rm, the supernatant was discarded, and cells were lysed by adding 200 μL of cell lysate for 30 minutes. Centrifuge at 1200 rm and take 50 μL/well of the supernatant in a 96-well plate to make 3 replicate wells. The reagent I50 μL/well and reagent II 50 μL/well were sequentially added to the kit, and incubated at 37 ° C, 5% carbon dioxide for 15 minutes, the fluorescence intensity was measured at the excitation wavelength (540 nm), and the OD value was calculated according to the control group and the blank group. , brought into the standard curve, calculate the release of nitric oxide. The experimental results are shown in Figure 1.

The above experiments show that the compounds synthesized in the present invention are capable of producing a relatively large amount of NO, indicating that the compound involved in the present invention can be used as a NO donor.

Claims (8)

1. A benzofuroxime oxide histone deacetylase inhibitor having the structure of Formula I or I', and the tautomer II of Formula I or the tautomer II of Formula I' ', an optical isomer, a mixture of diastereomers and racemates, a pharmaceutically acceptable salt, solvate or prodrug thereof;

   

   among them,

   X is oxygen or an amino group;

   R ₁ is a saturated aliphatic chain of various C1-8, a branched saturated aliphatic chain, an olefin chain, an alkyne chain, an alkoxy chain, an aroyl group, a heteroaryl group, a cycloalkyl group, a C1-8 heteroalkyl group. An aromatic group having a substituent or a heteroaryl group having a substituent;

   R ₂ is hydroxamic acid, hydroxy, carboxy, methoxycarbonyl, amido, hydrazide or N-(2-aminophenyl)amide;

   R ₃ represents a hydrogen, ortho, meta, or parafluoro, chloro, bromo, iodo halogen, hydroxy, amino, methoxy, ethoxy, or cyano group.
2. The benzofurazan oxide histone deacetylase inhibitor according to claim 1, wherein

   X is oxygen;

   R ₁ is a saturated aliphatic chain of C1-8, an unsaturated aliphatic chain of C1-8, an aromatic chain of C1-9, a fatty chain containing a hetero atom of C1-8, and a heterocyclic ring of C1-9;

   R ₂ is a hydroxyl group, a carboxyl group, a methoxycarbonyl group, an ethoxycarbonyl group, a hydroxamic acid;

   R ₃ is hydrogen.
3. The compound according to claim 1 or 2, which is one of the following compounds:

   5-((4-(hydroxyamino)-4-oxobutyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (5a);

   5-((5-(hydroxyamino)-5-oxopentyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (5b);

   5-((6-(hydroxyamino)-6-oxohexyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (5c);

   5-((7-(hydroxyamino)-7-oxoheptyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (5d);

   5-((8-(hydroxyamino)-8-oxooctyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (5e);

   4-((4-(hydroxyamino)-4-oxobutyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (10a);

   4-((5-(hydroxyamino)-5-oxopentyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (10b);

   4-((6-(hydroxyamino)-6-oxohexyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (10c);

   4-((7-(hydroxyamino)-7-oxoheptyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (10d);

   4-((8-(hydroxyamino)-8-oxooctyl)carbonyl)benzo[c][5]oxadiazole-1-oxide (10e);

   5-((3-carboxypropoxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (4a);

   5-((4-carboxybutoxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (4b);

   5-((5-carboxypentyloxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (4c);

   5-((6-carboxyhexyloxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (4d);

   5-((7-carboxyheptyloxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (4e);

   4-((3-carboxypropoxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (9a);

   4-((4-carboxybutoxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (9b);

   4-((5-carboxypentyloxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (9c);

   4-((6-carboxyhexyloxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (9d);

   4-((7-carboxyheptyloxy)carbonyl)benzo[c][5]oxadiazole-1-oxide (9e);

   5-((4-hydroxybutoxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (3a);

   5-((5-hydroxypentyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (3b);

   5-((6-hydroxyhexyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (3c);

   5-((7-hydroxyheptyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (3d);

   5-((8-hydroxyoctyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (3e);

   4-((4-hydroxybutoxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (8a);

   4-((5-hydroxypentyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (8b);

   4-((6-hydroxyhexyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (8c);

   4-((7-hydroxyheptyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (8d);

   4-((8-hydroxyoctyloxy)carbonyl)benzo[c][1,2,5]oxadiazole 1-oxide (8e);

   5-((5-(Hydroxyamino)-4-oxopentyl)carbamoyl)benzo[c][1,2,5]oxadiazole-1-oxide (12a)

   5-((5-(Hydroxyamino)-5-oxopentyl)carbamoyl)benzo[c][1,2,5]oxadiazole-1-oxide (12b)

   5-((5-(Hydroxyamino)-6-oxopentyl)carbamoyl)benzo[c][1,2,5]oxadiazole-1-oxide (12c)

   5-((5-(Hydroxyamino)-7-oxopentyl)carbamoyl)benzo[c][1,2,5]oxadiazole-1-oxide (12d)

   5-((5-(Hydroxyamino)-8-oxopentyl)carbamoyl)benzo[c][1,2,5]oxadiazole-1-oxide (12e)

   5-((5-((2-Aminophenyl)amino)-4-oxopentyl)oxy)carbonyl)benzo[c][1,2,5]oxadiazole-1-oxide ( 13a);

   5-((5-((2-Aminophenyl)amino)-5-oxopentyl)oxy)carbonyl)benzo[c][1,2,5]oxadiazole-1-oxide ( 13b);

   5-((5-((2-Aminophenyl)amino)-6-oxopentyl)oxy)carbonyl)benzo[c][1,2,5]oxadiazole-1-oxide ( 13c);

   5-((5-((2-Aminophenyl)amino)-7-oxopentyl)oxy)carbonyl)benzo[c][1,2,5]oxadiazole-1-oxide ( 13d);

   5-((5-((2-Aminophenyl)amino)-8-oxopentyl)oxy)carbonyl)benzo[c][1,2,5]oxadiazole-1-oxide ( 13e);
4. A process for the preparation of a compound according to claim 1, characterized in that the step is one of the following:

   4-amino-3-nitrobenzoic acid was used as a raw material, and the key intermediate 2 was obtained by azide nitridation and rearrangement reaction, followed by esterification reaction to obtain carboxylic acid compound 4a-4e, and finally formed by condensation of hydroxylamine hydrochloride. Target product hydroxamic acid 5a-5e;

   The synthetic route is as follows:

   

   or

   2-Amino 3-nitrobenzoic acid was used as raw material, and the key intermediate 7 was obtained by azide nitridation and rearrangement reaction. After esterification, it was oxidized to obtain carboxylic acid compound 9a-9e. Finally, it was made by condensation of hydroxylamine hydrochloride. Target product hydroxamic acid 10a-10e;

   The synthetic route is as follows:

   

   The reagents in the above synthetic route are: (a) sodium nitrite, hydrochloric acid, sodium azide; (b) toluene; (c) C4-C8 linear primary diol, PyBOP, triethylamine; (d) Jones reagent, acetone; (e) isobutyl chloroformate, triethylamine, tetrahydrofuran; hydroxylamine hydrochloride, potassium hydroxide, methanol;

   R ₁ and R _{3 are} as defined in the above formulas I and I'.
5. A method of preparing a compound according to claim 1, further comprising the following subsequent synthetic route:

   The subsequent synthetic route three is as follows:

   

   The reagents in the above synthetic route are: (a) NH ₂ (CH ₂ ) _n COOCH ₃ , n = 3-7, PyBOP, triethylamine; (b) potassium hydroxylamine, anhydrous methanol;

   Or, the subsequent synthetic route is as follows:

   

   The reagent in the above reaction scheme: (a) o-phenylenediamine, EDC, DMAP, triethylamine, anhydrous dichloromethane;

   R ₁ and R _{3 are} as defined in the above formulas I and I'.
6. Use of a compound according to any one of claims 1 to 3 for the preparation of a medicament for preventing or treating a mammalian disease associated with abnormal expression of histone deacetylase activity; said abnormal expression of histone deacetylase activity Related mammalian diseases include: cancer, neurodegenerative diseases, viral infections, inflammation, leukemia, malaria or diabetes.
7. A pharmaceutical composition suitable for oral administration to a mammal comprising a compound of any of claims 1-3 and one or more pharmaceutically acceptable carriers or excipients.
8. A pharmaceutical composition suitable for parenteral administration to a mammal comprising a compound of any of claims 1-3 and one or more pharmaceutically acceptable carriers or excipients.

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