DE1620620B2 - Process for the preparation of 7-chloro-7-deoxylincoraycin and -epilincomycin and their isomers and analogs - Google Patents

Description

in which R is an alkyl group with no more than 20 carbon atoms, a cycloalkyl group with 3 to at most 8 carbon atoms or an aralkyl group with at most 12 carbon atoms, HR ₁ an alkylidene radical hydrogenated at the alkylidene double formation of no more than 20 carbon atoms, a correspondingly hydrogenated cycloalkylidene radical with 3 to 8 carbon atoms or a correspondingly hydrogenated aralkylidene radical with a maximum of 12 carbon atoms and R _{3 in} addition to the meanings of HR ₁ denotes a hydrogen atom, as well as their acid addition salts, characterized in that a compound of the general formula II

(Π)

in which X is a hydrogen atom or an ayl radical (one of the general formulas A, B, D or E means

(A)

(D)

(B)

(E)

in which ReStR ₁ denotes an alkylidene, cycloalkylidene or aralkylidene radical corresponding to ReStHR _{1 , the radical R 2} has the meaning given for this radical independently of HR _{1 , the radicals HR 1} and R _{3 have} the above meaning and Z is hydrogenolytically denotes removable hydrocarbonoxycarbonyl protective group, or a corresponding acid addition salt, optionally under an inert gas atmosphere and in an inert solvent, with at least. Moles of thionyl chloride reacted and the reaction mixture kept moving at room temperature until an almost clear solution is obtained, this is then heated to a temperature of 50 to 100 "C for about 1 to 5 hours, this formed, chlorinated in the 7-position Sulphite intermediate, optionally after its isolation, alcoholized in a manner known per se or hydrolyzed with sodium hydroxide solution, the compound thus obtained, optionally in a manner known per se, either by catalytic hydrogenation, by hydrogenolysis and optionally subsequent reductive alkylation or by introducing an acyl radical The above general formulas A, B, D, E and subsequent conversion of the radicals A, D or E are converted into a free base of the general formula I by the methods mentioned above and this is optionally converted into an acid addition salt.

The invention relates to a process for the preparation of 7-chloro-7-dcoxylincomycin and 7-chloro

7-deoxyepilincomycin and its analogs and isomers of the general formula

(I)

OH

in which R is an alkyl radical with up to 20, preferably less than 8 carbon atoms, a cycloalkyl radical with 3 to at most 8 carbon atoms or an aralkyl radical with at most 12 carbon atoms, preferably at most 8 carbon atoms. HR _{1 is} an alkylidene radical hydrogenated on the alkylidene double bond and having a maximum of 20 carbon atoms (including methylene), preferably a maximum of 8 carbon atoms, a correspondingly hydrogenated cycloalkylidene radical having 3 to a maximum of 8 carbon atoms or a correspondingly hydrogenated aralkyl

10

25 lidene radical with a maximum of 12 carbon atoms, preferably a maximum of 8 carbon atoms, and R _{3 in} addition to the meanings of the radical HR ₁ denotes a hydrogen atom, and their acid addition salts.

The method according to the invention is in the claim described. In this process, an unforeseeable event takes place according to the following Reaction scheme, stepwise selective chlorine substitution in the 7-position with epimerization instead, with no thionyl chloride in the first stage, e.g. according to WJ. Hickinbottom, “Reactions of Organic Compounds ", 3rd ed. 1957, p. 128, expected substitution of a hydroxyl group by Chlorine, but rather a substitution of two hydroxyl hydrogen atoms through conversion with one mole of thionyl chloride through the OS <group with the formation of an isolable, unchlorinated 3,4-cyclic sulfite XVIIa takes place, which in a further stage with further thionyl chloride to the likewise isolable, 7-position chlorine-substituted 3,4-cyclic sulfites XVIIb and XVIII, the latter being a bis- (3,4-cyclic Sulfite) sulfite is implemented (see. Example 9). Assuming a 7-hydroxy compound with e.g. L-threoconfiguration, the corresponding 7-chloro-7-deoxy compound is formed after alcoholysis of the sulfite obtained with D-erythro configuration.

SOCl,

OH

(Π)

(XVIIa)

O = S

(XVIII)

H,

(NaOH)

OH

(XVIIb)

Examples of alkyl radicals (R, and HR ₁ ) with a maximum of 20 carbon atoms are methyl, ethyl, propyl butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, Tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl. Nonadecyl and eicosyl radicals and their isomers

OH

(D

To shape. Examples of cycloalkyl radicals are the cyclopropyl, Cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, 2-methylcyclopentyl, 2,3-dimethylcyclobutyl, 2-methylcyclobutyl and 3-cyclopentylpropyl radical. Examples of aralkyl radicals are benzyl, phenethyl, 3-phenylpropyl and 1-naph-

'5

methylmethyl radical. Suitable alkylidene, cycloalkylidene and aralkylidene groups R ₁ are, for example, the methylene, ethylidene, propylidene, butylidene, pentylidene, hexylidene, heptylidene, octylidene, nonylidene, decylidene, undecylidene. Dodecylidene, tridecylidene, tetradecylidene. Pentadecylidene, hexadecylidene, heptadecylidene, octadecylidene, nonadecylidene, eicosylidene groups and their isomeric forms, cyclopropylidene, cyclobutylidene, cyclopentylidene, cyclohexylidene, cycloheptylidene, cyclooctylidene, 2-cyclopentylpropylethyl. Benzylidene, 2-phenylethylidene. 3-phenylpropylidene and 1-naphthylmethylene.

The reaction is advantageously carried out in an inert atmosphere, for example under nitrogen. Carbon tetrachloride, in addition to other inert solvents such as chloroform, methylene chloride, ethylene chloride, ether or benzene, can be used as the solvent. In the - preferred - use of carbon tetrachloride as solvent, its reflux temperature (JTC) is expediently chosen as the reaction temperature. After the reaction has ended, it is advantageously allowed to cool under nitrogen. The precipitated material is isolated and dried. The solvent is removed in vacuo at flask temperatures of preferably less than about 35 ° C., and the product which precipitates out is collected, dried and then treated with ethanol in order to convert the sulfite intermediates into the desired end product. The material obtained in this way can be further purified by solvent extraction and / or recrystallization; it can be isolated as a free base or in the form of an acid addition salt.

Larger amounts than 3 moles of thionyl chloride per mole of starting compound can be used however, it is usually neither necessary nor desirable, more than about ten times To use excess. It is expedient to use an excess of 2 to 3 times the amount. the The amount of solvent is not critical and depends on the particular needs of the practice. Usually About 15 to 30 parts by volume of solvent per part of the solid starting compound are sufficient. However, the ratio of solvents to thionyl chloride is important because of the solubility of the product in thionyl chloride. When the volume ratio of solvent to thionyl chloride is high, it falls the desired product on cooling the reaction mixture and the work-up is thereby simplified. For example, when using carbon tetrachloride, a product mixture falls directly into the Cool down the reaction mixture if the volume ratio of carbon tetrachloride is too Thionyl chloride is maintained at about 10: 1.

The compounds obtainable from the starting compounds of the general formula IIA are with a catalyst for the hydrogenation of olefinic double bonds to the corresponding compounds of formula I hydrogenated, with a mixture of cis and trans epimers according to the following general Formulas III and IV apply:

(HA)

OH

(III)

which can optionally be separated by countercurrent distribution or by chfomätographischcn ways can. If desired, the starting compounds of the general formula HA in

those of the general formula IIB are converted.

CH,

(HB)

The compounds of general formula I in which R _{3 is} hydrogen can be prepared in a manner known per se by alkylation, for. B. by reacting them with an oxo compound (aldehyde or ketone) and hydrogenating the adduct formed in the presence of a suitable catalyst such as platinum or palladium, converted into their homologues in which R _{3 is} an alkyl group; just like the starting compounds of the general formula IIB (cf. Example 4, Part Gl and H 1). Suitable oxo compounds have the formula R ₄ R ₅ CO, in which the ReStR ₄ R ₅ C has the meaning of R ₁ .

The starting compounds of the general formulas HA and HB can be obtained by a compound of the general formula V

35

(V)

40

45

OH

in which R has the aforementioned meaning, with a 4-substituted-L-2-pyrrolidinecarboxylic acid of the general Formula A or B acylated. The acylation can be carried out by methods that are used for the acylation of Aminosugars are known per se.

The starting acid of the formula A can be prepared by adding a 4-oxo compound of the formula

(C)
C-OH

'/ I Il ο ο

in the Z a hydro-

carbyloxycarbonyl protecting group, in a manner known per se with a Wittig reagent, e.g. an alkylidene triphenylphosphorane (see Ber., Vol. 87, p. 1348 [1954] Quarterly Reviews, Vol. XVII. No. 4, p. 406 [1963]). Examples of hydrocarbyloxycarbonyl groups Z are benzyloxycarbonyl groups the general formula

Il

CH, OC-

in which Y represents hydrogen, a nitro or methoxy group, chlorine or bromine.

When carrying out this process, the 4-oxo-L-2-pyrrolidinecarboxylic acid (formula C) is the freshly prepared Wittig's reagent was added. The Wittig reagent used here can by the following general formula can be reproduced

R ₁ = P (C ₆ H ₅ ),

in which R _{1 has} the above meaning. These Wittig reagents are obtained by reacting an alkyl. Cycloalkyl or aralkyl triphenylphosphonium halide with a base such as sodium amide or sodium or potassium hydride or the sodium or potassium metallate of dimethyl sulfoxide. The reaction is generally carried out in an organic solvent such as benzene, toluene, ether, dimethyl sulfoxide or tetrahydrofuran, at temperatures between 10 ° C. and the reflux temperature of the reaction mixture. The product thus obtained, a 4-alkylidene-4-cycloalkylidene- or 4-aralkylidene-1-protected-L-proline of the general formula D.

(D)

is isolated from the reaction mixture in a customary manner, generally by extraction from aqueous Solutions of the reaction mixture. The crude product can be purified in a conventional manner

be, for example by recrystallization, chromatography with the formation and purification of easily prepared derivatives such as the amine salts, e.g. Dicyclohexylamine salts, and the like, whereupon the amino acids are liberated from these compounds.

By hydrogenating an acid of the formula D in the presence of a catalyst such as. B. Platinum, which is the saturation promotes a double bond, but does not cause hydrogenolysis, a compound of the all-

409 539/357

common formula E.

(E)

IO

obtain. For example, one can use platinum on a support such as carbon or a crosslinked polystyrene trimethylbenzylammonium resin in hydroxyl form. If desired, the starting compounds of the general formula V are acylated with acids of the formulas C, D or E with formation of compounds HC, HD and IIE, (i.e. the corresponding N-acylation products of the amino sugars of the general formula II). Then you can convert the compound IIC into the compound HD by treatment with a Wittig reagent and hydrogenate HD to form compound IIE. The hydrogenation of both the acid D and the acylate HD also leads to a mixture of cis and trans epimers, which, if desired, is carried out Countercurrent distribution or chromatography can be separated.

The starting acids of the general formula B, in which R _{3 represents} hydrogen, are obtained when an acid of the general formula D or E is subjected to hydrogenolysis in the presence of a palladium catalyst, for example palladium on carbon. Likewise, compounds of the general formulas IID and HE are converted into compounds of the general formula IIB in which R ₃ denotes hydrogen. Starting acids of the general formula B in which R _{3 is} hydrogen, as well as compounds of the formula IIB where R ₃ = hydrogen, can be converted into compounds of the formulas B and IIB in which R _{3 is} the radical HR _{1 by the processes mentioned above} will. The starting acids of the general formula A are obtained by treating an acid of the general formula D with hydrogen bromide in acetic acid with removal of the group Z and replacement of the hydrogen in the N position by a group HR ₁ in the manner described above. Compounds of the general formulas HD and IIE are converted into compounds of the general formulas HA and IIB by the same procedure.

The compounds of the general formula I. and the starting compounds of the general formulas HA, IIB, and V exist both in protonicrter as also non-protonated form, depending on the pH of the environment. The protonated form is used as an acid addition salt, the non-protonated form is called the free base. The free bases can with appropriate Acids at pH values below about 7.0, advantageously at pH values from about 2 to 6, in stable Acid addition salts are transferred. Suitable acids for this purpose are e.g. B. hydrochloric acid. Sulfuric acid, Phosphoric acid, thiocyanic acid, fluorosilicic acid. Hexafluoroarsenic acid, hexafluorophosphoric acid, Acetic acid, succinic acid, citric acid, lactic acid, maleic acid. Fumaric acid, pamoic acid, cholic acid, Palmitic acid, mucic acid, camphoric acid. Glutaric acid, glycolic acid, phthalic acid, tartaric acid. Lauric acid, stearic acid, salicylic acid, 3-phenylsalicylic acid, 5-phenylsalicylic acid, 3-methylglutaric acid, Orthosulfobenzoic acid, cyclopentane propionic acid, 1,2-cyclohexanedicarboxylic acid, 4-cyclohexanecarboxylic acid, Octadecenyl succinic acid, octenyl succinic acid, methanesulfonic acid, benzenesulfonic acid, Helianthic acid, Reinecke's acid, dimethyldithiocarbamic acid, Cyclohexylsulfamic acid, hexadecylsulfamic acid, octadecylsulfamic acid, sorbic acid, Monochloroacetic acid, undecylenic acid, 4'-hydroxyazobenzene-4-sulfonic acid, Octadecylsulfuric acid. Picric acid, benzoic acid or cinnamic acid.

The acid addition salts can be used for the same purposes as the free bases; even you can use them to clean the free bases. For example, a free base in itself known way into a water-insoluble salt. e.g. the picrat, which then, e.g. Solvent extraction and washing, chromatography, fractionated liquid-liquid extraction or crystallization, is purified, whereupon the free base is released again by treatment with alkali will; another salt can also be obtained by metathesis. You can also use the free base in a water soluble salt, e.g. B. the hydrochloride or sulfate, transfer, and the aqueous solution of the Extract the salt with various water-immiscible solvents before the free base is regenerated.

The close analogs of T-chloro-V-deoxy-lincomycin, ie those compounds of general formula I in which R ₁ H is an alkyl group in cis or trans with not more than 8 carbon atoms, R _{3 is} hydrogen, methyl or ethyl and R is an alkyl group having not more than 8 carbon atoms have antibacterial properties comparable or superior to those of lincomycin; they can be used for the same purposes as lincomycin.

Some of the starting compounds of the general formula II can be obtained biosynthetically. Lincomycin [Methyl-6.8-dideoxy-6- (trabs-l-methyl-4-propyl-L-2-pyrrolidinecarboxamido) -l-thio-D-ery- thro-a-D-galacto-octopyranoside] can be obtained by the method of U.S. Patent 3,086,912 will. It has the general formula VI

OH

in which R and R, methyl groups and R ₁ H are a propyl group. Lincomycin B, [methyl-6,8-dideoxy-6- (trans-1-methyl-4-ethyl-L-2-pyrrolidinecarboxamido) -1-thio-D-erythro-aD-galacto-octopyranoside] (general

my formula VI with R and R ₃ = methyl and R ₁ H = ethyl) can also be obtained by the method according to US Pat. No. 3,086,912. Lincomycin C [S-ethyl-S-demethyl-lincomycin or ethyl-6,8-dideoxy-6- (trans-1-methyl-4-propyl-L-2-pyrrolidinecarboxamido) -l-thio-D-erythro-aD galacto-octopyranoside] (general formula VI with R = ethyl, R ₁ H = PrOPyI, R ₃ = methyl) can be obtained by carrying out the process of US Pat. No. 3,086,912 in the presence of added DL-ethionine. Lincomycin D [MethyI-6,8-dideoxy-6- (trans-4-propyl-L-2-pyrrolidinecarboxamido) -1 -thio-D-erythro-aD-galacto-octopyranoside] (general formula VI with R = methyl, R ₁ H = propyl and R ₃ = hydrogen) is obtained when the process according to US Pat. No. 3,086,912 in the presence of methyl-o-amino-o ^ -dideoxy-D-erythro-1-thio-aD- galacto-octopyranoside (hereinafter referred to as “oc-MTL” for short), a compound obtainable according to US Pat. No. 3,179,595 by hydrazinolysis of licomycin. N-Demethyllincomycin B [methyl-6,8-dideoxy-6- (trans-4-ethyl-L-2-pyrrolidinecarboxamido) -l-thio-D-erythroa-D-galacto-octopyranoside] (general formula VI with R = Methyl, R ₁ H = AUIyI and R ₃ = hydrogen) is also formed when the fermentation according to US Pat. No. 3,086,912 a-MTL is added. Lincomycin K [ethyl-6,8-dideoxy-6- (trans-4-propyl-L-2-pyrrolidincarboxamido) -l-thio-D-erythro-aD-galacto-octopyranoside] (general formula VI with R = ethyl, R ₁ H = PrOPyI and R ₃ = hydrogen) can be obtained by the fermentation according to US Pat. No. 3,086,912 in the presence of ethyl-o-amino-o ^ -dideoxy-l-thio-D-erythro- oe-D-galacto-octopyranoside (hereinafter referred to as "a-ETL"), a compound obtainable by hydrazinolysis of licomycin C [S-ethyl-S ^ -didemethyllincomycin B]. Ethyl-6,8-dideoxy-6- (trans-4-ethyl-L-2-pyrrolidincarboxamido-l-thio-D-erythro- aD-galacto-octopyranoside) (general formula VI with R = ethyl, 1H = ethyl and R ₃ = hydrogen), can be obtained if the fermentation according to US Pat. No. 3,086,912 a-ETL is added.

The above-described N-demethyl compounds, which are obtained when α-MTL and α-ETL are added to the fermentation according to US Pat. No. 3,086,912, are examples of starting compounds of the formula IIB in which R _{3 is} hydrogen. By replacing the N hydrogen atoms in compounds of the formula HB by the method described above, corresponding compounds with R ₃ = HR _{1 are obtained} .

Lincomycin or starting compounds of the general Formula II with D-erythro configuration can be modified by oxidation of the 7-hydroxyl group Protecting the 3,4 ^ hydroxyl groups, e.g. B. by reaction with acetone to form the 3,4-isopropylidene derivative to a 7-oxo group and Reduction of the oxo group, e.g. with sodium borohydride to the hydroxyl group in the corresponding > bindings with L-threo configuration are transferred.

For example, lincomycin when treated with acetone in the presence of p-toluenesulfonic acid gives 3.4-O-IsopropyIidenlincomycin, which by oxidation with chromium oxide in 7-dehydro-3,4-O-isopropylideneincomycin [methyl-o ^ -dideoxyO ^ -O-isopropylideno-ttrans-l-methyM-propyl-L ^ -pyrrolidinecarboxami- do) -l-thio-D-glycero-a-D-galacto-octanopyranos-7-ulosid] is transferred, which in turn is carried out by Treatment with borohydride in 7-epilincomycin [methyl-6,8-dideoxy-6- (trans-l-methyl-4-propyl-L-2-pyrrolidinecarboxamido) -l-thio-L-threo-a-D-galacto-octopyranoside] is converted.

The biosynthetically produced lincomycins which can be used as starting materials in the process according to the invention and the amino sugars produced therefrom are either methyl or ethyl thioglycosides; they can, like both the corresponding starting compounds of the general formulas IIA, IIB, IIC and IIE or V and the end products of the general formula I, if desired, can be converted into higher or lower glycosides by converting them (cf. Example 3, Part B) with a mercaptan of the general formula R ₆ SH, in which R _{6 is} an alkyl radical having not more than 20 carbon atoms, which differs by one carbon atom from R, and the dithioacetals formed with ring opening then by treatment with an acid or by heating , in the presence or absence of acid, cyclized again, with compounds of the general formulas HA, IIB, IIC. IIE, V or I are obtained, but in which the substituent R has been replaced by R ₆ .

These products can be subjected to hydrazinolysis for deacylation (cf. Example 4, Part D). whereby compounds of the formula V, in which, however, R has been replaced by R ₆ , are obtained, which in turn can be acylated with acids of the formulas A, B, C, D and E by the processes described above. For example, a-MTL can be converted into a-ETL by treatment with ethyl mercaptan and cyclization.

Another process for the preparation of compounds of the general formulas I, II or V, in which the substituent R has been replaced by another alkyl substituent R ₆ , consists in brominating the starting material of the general formulas I, II or V and then the product with a mercaptan of the general formula R ₆ SH (see. Example 3, part C).

The respective starting compound is dissolved in water in the form of a soluble salt, for example the hydrochloride, whereupon bromine is added ^{with cooling, preferably to about -10 to 20 ° C.} It is sufficient if the aqueous solution is ^{cooled to about 0 °} C. and bromine is added dropwise. The stoichiometric amount of bromine is 1 mole per mole of starting compound; however, an excess or a shortfall can be used. It is expedient to work with a small excess of bromine of about 25%. The bromine initially replaces the RS group and the resulting intermediate hydrolyzes to the sugar in which the pyranose form is in equilibrium with the aldose form. In the presence of acid, for example hydrochloric acid or another strong, non-oxidizing acid such as p-toluenesulfonic acid or sulfonic acid anion exchange resins, the mercaptan R ₆ SH reacts with the sugar to form the desired thioglycoside. At the same time, some diacetal can be formed which, after separation, as described above, can be cyclized to form the desired thioglycoside.

In the following examples, for a more detailed explanation serve the method according to the invention.

Parts and percentages relate to weight and solvent ratios relate to volume, unless otherwise stated.

example 1

7- (S) -chloro-7-deoxylincomycin

[Methyl-7-chloro-6,7,8-trideoxy-6- (trans-1 '-methyl-

4-propyl-L ^ -pyrrolidincarboxamido) -1 -thio-

L-threo-a-D-galacto-octopyranoside]

(XIX)

SCH ₃

OH

A. The free base activity: about 4 to 8 times that of lincomycin. The antibacterial spectrum is that of lincomycin same.

Example 2

7- (S) -chloro-7-deoxylincomycin, free base

The procedure of Example 1, Part A was repeated with the difference that methylene chloride was used as an extractant in place of ether; the combined extracts were filtered and evaporated to dryness. 64% of 7-chloro-7-deoxylincomycin were obtained (free base) as a yellow amorphous solid. 15 g of this solid were added to 30 g of silica gel adsorbed in methylene chloride, dried and applied to a column filled with 1500 g of silica gel and was 7.5 cm in diameter. The column was with a mixture of methanol and Chloroform in a ratio of 1:19 with portions of 200ml, after 2 liters forerun, eluted. The factions 26, 27 and 28 were poured together and evaporated to dryness, leaving 1.04g of essentially pure 7-chloro-7-deoxylincomycin in the form of an amorphous solid with an anti-bacterial Spectrum which was the same as that of 7-chloro-7-deoxylincomycin hydrochloride according to Example 1 was obtained.

20th

A suspension of 221.0 g (0.5 mol) of lincomycin hydrochloride in 5 liters of carbon tetrachloride was added Stirred well under nitrogen at 25 ° C. Then 900 ml of thionyl chloride were added all at once, whereupon was stirred for a further 2 hours. During this time the solid dissolved and a clear one was obtained Solution; The reaction mixture was refluxed for 2 hours, after which the heat source removed and nitrogen was passed into the amber solution until the flask temperature rose to 25 ° C ■ had fallen. Then about 4 liters of the liquid were removed by vacuum distillation at flask temperature less than 35 ° C away. The yellow solid which separates out during the distillation was collected and dried. It was dissolved in about 300 ml of methanol, the solution was brought to 25 ° C cooled, adjusted to pH 11 with dilute aqueous sodium hydroxide solution '(2normal), with water diluted to about 1200 ml and extracted well with ether. The ether extracts were combined with a minor one Washed amount of water, dried over anhydrous magnesium sulfate and nitrated. When evaporating some of the combined ether extracts became 7-chloro-7-deoxylincomycin (free, base) as yellow amorphous solid obtained.

Example 3

7-chloro-7-deoxylincomycin C

[Ethyl-7-chloro-6,7,8-trideoxy-6- (trans-l-methyl-

4-propyl-L-2-pyrrolidinecarboxamido) - 1-thio-

L-threo-a-D-galacto-octopyranoside]

PCX)

NS,

OH

B. hydrochloride

When hydrogen chloride gas was added to the filtrate according to Part A, 7-chloro-7-deoxylincomycin hydrochloride precipitated, which was separated off and recrystallized from ethanol and ethyl acetate. The white, crystalline hydrochloride was obtained in 32% yield, solvated with about 1 mol of water.
Analysis for C ₁₈ H ₃₃ ClN ₂ O ₅ S · HCl · H ₂ O:
Calculated C45.18; H7.37; Cl 14.82; N5.86; S6.70;
H ₂ O 3.77;

found: C, 44.70; H 7.65; Cl 14.27; N 5.78;
S 6.45; H ₂ O 3.85.

[ate ⁵ : + 130 "(c = 0.9858 g / 100 ml, H ₂ O)

A. Chlorination of Lincomycin C

A suspension of 1 g of lincomycin C hydrochloride in 25 ml of carbon tetrachloride and 4.5 ml of thionyl chloride was stirred at 25 ° C. for 2 hours under nitrogen. A clear solution was obtained within about 15 minutes. The reaction mixture was then boiled for 2 hours under reflux and evaporated to dryness in vacuo to give a yellow solid, which was dried for 18 hours at 40 ⁰ C in vacuo. The product was then dissolved in about 15 ml of warm ethanol, made basic with sodium hydroxide as described in Example 1 and diluted to 300 ml with water. The aqueous solution was extracted five times with 100 ml of ether each time. The ether extracts were combined, dried over magnesium sulfate, filtered and washed with chlorine

saturated hydrogen gas, which was then evaporated; Abei obtained a brown residue which, when recrystallized twice from a mixture of ethanol and ethyl acetate (dissolving in the smallest amount of ethanol and adding ethyl acetate until the onset of cloudiness), 200 mg of 7-chloro-deoxylincomycin C hydrochloride in the form white crystals, [α] " ² ° = + 136 °; this product had the same activity and the same antibacterial spectrum as the V-chloro-V-deoxylincomycin hydrochloride according to Example 1.

The starting compound lincomycin C was prepared by one of the following two processes (B) or (C) r, either (B) by reacting lincomycin with ethanethiol to form the ) iäthyldithioacetals of the following formula XXI reaction B1) and cyclization of the same with Erlitzen of the reaction mixture in the presence of) -toluenesulfonic acid or heating until it melts Reaction B2), or (C) by brominating linconycin and implementation with Athanthiol. Lincomycin C: ann also according to US Pat. No. 3,086,912 Hologically obtained in the presence of DL-ethionine will.

The two procedures are described in more detail below:

B. Preparation of Lincomycin C

B 1. 6,8-Dideoxy-6- (trans-l'-methyl-4'-propyl-L ^ -pyrrolidincarboxamido ^ D-erythro-D-galacto- aldehydo-octose diethyldithioacetal

CH,

35

40

45

(XXl)

In a 1-liter three-necked flask 150 mL of concentrated hydrochloric acid and 50 ml Äthanthiol were (previously chilled to 0 ⁰ C) is introduced, whereupon 15.0 g of lincomycin hydrochloride were added. After stirring with a magnetic stirrer for 5 hours, the mixture was diluted with an equal volume of ice water, after which it was carefully extracted with a technical hexane mixture; the extracts were discarded.

Most of the acid was neutralized by carefully adding solid potassium hydroxide (100 g), the temperature of the well-stirred reaction mixture being kept between 20 and 30 ° C. by cooling with dry acetone ice. Solid potassium chloride was filtered off and washed with chloroform. Additional chloroform (about 150 ml) was added to the filtrate and the mixture was adjusted to pH 10 by adding aqueous sodium hydroxide (2N) while stirring with a magnetic stirrer. The chloroform layer was separated, the aqueous layer was carefully extracted with chloroform, the combined extracts were washed twice with water, then dried over anhydrous sodium sulfate. Upon removal of the solvent at about 3O ⁰ C in vacuo a semisolid residue which, after crystallization from acetone, 5.41 g of 6,8-dideoxy-6- (trans-r-methyl-4'-propyl-L-2 was obtained pyrrolidincarboxamido) -D-erythro-D-galacto-aldehydo-octose-diethyldithioacetal in the form of colorless, flattened needles with a melting point of 130 to 132 ° C. Concentration of the mother liquors gave a further 1.50 g of the product with a melting point of 129 to 131 ° C. (total yield 6.91 g, 42.4%).

Analysis for C ₂₁ H ₄₂ N ₂ O ₆ S ₉ :

Calculated C, 52.25; H 8.77; N 5.81; S 13.29%;

Found: C, 52.38; H 8.71; N 5.93; S 13.46%.

B2. Cyclization to Lincomycin C

(a) One part each of diethyldithioacetal (according to Part B1) and p-toluenesulfonic acid monohydrate were in 25 parts of acetonitrile are refluxed until a substantial antibacterial effect is obtained from the product had been. The reaction mixture was cooled, evaporated to dryness and then on Chromatographed silica gel, 100 parts of silica gel per 1 part of the product and a solvent mixture from ethyl acetate, acetone and water in a ratio of 8: 5: 1. The parliamentary groups 102 bis 131 showed antibacterial effects. Fractions 106 to 125 were combined, evaporated to dryness and crystallized from acetone acidified with hydrochloric acid; Recrystallize by dissolving in water and Addition of acetone. This gave crystals of lincomycin C hydrochloride with a melting point of 149 up to 153 ° C.

(b) The Diäthyldithioacetal under Part B1 was heated to 260 ⁰ C for about 3 minutes, the smell of ethylmercaptan was perceived. After chromatography as described in Part B2 (a), the product gave lincomycin C.

C. Another method of making
Lincomycin C

8.85 g (0.02 mol) Lincomycin hydrochloride were dissolved in 20 ml of water, cooled to 0 ⁰ C and im_ under stirring with 3.52 g (0.022 mol) of bromine were added to the course 1 minute. Then 25 ml of ethanethiol were added and the mixture was stirred at 25 ° C. for 2 hours. The clear, colorless 2-phase system

(Ethanethiol is relatively insoluble in water) was cooled in an ice bath and hydrogen chloride gas was bubbled in for about 5 minutes. The lower, aqueous phase turned red. The reaction mixture was then extracted three times with 100 ml of a technical hexane blend, and aqueous sodium ^hydroxide: solution was added to the aqueous phase to a pH value of 11 set. The basic phase was extracted well with chloroform, the chloroform extracts were washed with saturated sodium chloride solution, dried and evaporated in vacuo to give 6.2 g of a white solid. 4.8 g of this solid were chromatographed on 800 g of silica gel, using the method in

409 539/357

Example 2 proceeded procedure described; methanol-chloroform was used as the solvent system (1: 7). After a first run of 800 ml, 80 fractions of 25 ml each were collected. The factions 40 to 58 were combined and evaporated to dryness and the remaining solid turned off Recrystallized acetone, 0.5 g of a material obtained, which according to the diethyldithioacetal Part B1 was identical. Fractions 65 to 75 were also combined, evaporated to dryness and dissolved in a mixture of 5 ml of methanol and 400 ml of diethyl ether. Hydrogen chloride gas was added, and the white solid which separated out was collected. After recrystallizing from aqueous acetone gave 0.5 g of lincomycin C hydrochloride.

Example 4

Methyl-7-chloro-6,7,8-trideoxy-6- (l-ethyl-4-butyl-

L-2-pyrrolidincarboxamido) -1 -thio-L-threo-

ü-D-galacto-octopyraniside

(cis and trans epimers)

CH,

Cl

CKXII)

SCH ₃

OH

Part A (chlorination in 7-position)

A suspension of 116 mg of methyl 6,8-dideoxy-6- (trans-r-ethyl-4'-butyl-L-2-pyrrolidinecarboxamido) -l-thio-D-erythro-aD-galacto-octopyranoside (cf. Part H) in 3 ml of carbon tetrachloride and 0.7 ml of thionyl chloride was stirred at 25 ° C. until a clear solution was obtained (approx. 15 minutes), whereupon the mixture was left to stand for 2 hours at 25 ° C. The reaction mixture was refluxed for 2 hours boiled and then evaporated to dryness in vacuo to give a yellow solid which was worked up as described in Example 3. However, the product did not crystallize, so that the solvents were evaporated off, giving 10 mg of methyl ^ -chloro-oJ. S-trideoxy-o-Orans-l'-ethyW-butyl-L-2-pyrrolidincarboxamido) -l-thio-L-threo-aD-. Galacto-octopyranoside-hydrochloride formula XXII with R ₃ = C ₂ H ₅ ) as buff-colored, amorphous Solid which has 8 times the activity of lincomycin against gram-positive bacteria and 16 to 64 times the activity of lincomycin against gram-negative bacteria e.

Elemental analysis (values calculated in brackets for C ₀ H ₃₈ Cl ₂ N ₂ O ₅ S):

C%: 48.38 (49.07); H%: 8.03 (7.83); N%: 5.56 (5.72); S%: 6.43 (6.55); Cl%: 15.06 (14.49); H, 0%: 3.02.

If you work with the cis-epimer, you get the methyl-7-chloro-6,7,8-trideoxy-6- (cis-l'-ethyl-4'-butyl-L-2-pyrrolidinecarboxamido) -l- thio-L-threo-aD-galacto-octopyranoside hydrochloride with a similar antibacterial spectrum and an optical rotation of [aß ⁵ = + 106 ° (H ₂ O).

The ice and ice cream used in the above example as starting materials for the process according to the invention trans-epimers were produced in stages (see Chapters B to H 2) as follows:

B. 4-butylidene-1-carbobenzoxy-L-proline
and its cyclohexylamine salt

19 g of sodium hydride (in the form of a 53% suspension in mineral oil) were heated to 70 to 75 ° C. with 350 ml of dimethyl sulfoxide until the reaction had ended (about 30 minutes). After cooling to 32 ° C., 16.2 g of butyltriphenylphosphonium bromide were added. The resulting reaction mixture was stirred for 1 hour to ensure complete reaction. Then a solution of 26 g of 4-keto-l-carbobenzoxy-L-proline was added in 100 ml of dimethylsulfoxide and the resulting mixture heated for 3 hours at 70 ⁰ C. The mixture was then cooled to 25 ° C. and 1 liter of 2.5% strength aqueous potassium bicarbonate solution was added. The resulting

The mixture was washed twice with 700 ml of ether each time, after which the ether was discarded it had been back extracted with 150 ml of 2.5% aqueous potassium bicarbonate solution. The bicarbonate solutions were combined and acidified with 4N hydrochloric acid. The acidified mixture was made four times extracted with 500 ml of ether each time. The combined ether extracts were successively with 250 ml of water, washed three times with 250 ml of saturated aqueous sodium bisulfite solution and with 250 ml of water and then dried over anhydrous sodium sulfate. When evaporating the solvent in vacuo 24 g of an oily residue were obtained from 4-butylidene-1-carbobenzoxy-L-proline.

This residue was dissolved in 31 ml of acetonitrile and mixed with 18 ml of dicyclohexylamine; then it was chilled. The crystals which separated out were collected, washed with acetonitrile and dried in vacuo, 21 g (46.8%) of crystalline dicyclohexylamine salt having a melting point of 136 to 140 ^° C. being obtained. After two recrystallizations from acetonitrile, an analytically pure sample with a melting point of 142 to 144 ° C .; optical rotation [a ⁵ : -4 ° (£ · = 0.99, CHCl ₃ ).

Analysis for C ₂₀ H ₄₄ N ₂ O ₄ :
Calculated: C71.86; H9.15; N5 / 78.
Found: C, 71.69; H 9.30; N 5.74.

10 g of the dicyclohexylamine salt were with ether and excess 5% aqueous potassium hydroxide

solution shaken until no more solid remained. The layers were separated and each was back washed. The aqueous-alkaline layer was combined with the washing solution of the ether layer and with . 4N hydrochloric acid acidified. The mixture was again

extracted with ether, the extracts were combined, dried over sodium sulfate and in vacuo. evaporated, 6.3 g (93%) of "4-butylidene-1-carbobenzoxy-L-proline received in the form of an oil.

C. 4-Butyl-1-carbobenzoxy-L-proline

The oil obtained according to Part B was dissolved in 200 ml of methanol over 2.1 g of 10% platinum on ion exchange resin hydrogenated at 2.8 atmospheres of hydrogen pressure. The catalyst was filtered off and that The filtrate was evaporated to give 6.3 g of 4-butyl-1-carbobenzoxy-L-proline received in the form of an oil. The product contained approximately 2 parts of cis -4-butyl-1-carbobenzoxy-L-proline per part of trans-4-butyl-1-carbobenzoxy-L-proline.

The 4-ylidene group can optionally be hydrogenated to a later, z. B. the last, procedural stage to be postponed.

D. methyl-o-amino-ojS-dideoxy-l-thio-

D-erythro-a-D-galacto-octopyranoside

(a-MTL)

20th

A solution of 40 g of lincomycin (U.S. Patent 3068 912) in 20 ml of hydrazine hydrate (98 to 100%) was refluxed for 21 hours; Excess hydrazine hydrate was under vacuum Removed nitrogen at steam bath temperature, a residue of a pasty crystal mass remaining. The residue was cooled, acetonitrile was added and the mixture was stirred until the crystals were suspended which were then collected on a filter and washed with acetonitrile and ether. the The yield of white, crystalline base after drying in vacuo at room temperature was 21 g (84%). Recrystallization was carried out by dissolving the free base in hot dimethylformamide and adding it an equal volume of ethylene glycol dimethyl ether.

The methyl-o-amino-o ^ -dideoxy-l-thio-D-erythroa-D-galacto-octopyranoside has a melting point of 225 to 228 ° C, optical rotation [aß ⁵ : + 276 ° (c = 0.768 water) ; pKa ': 7.45.

Analysis for QH ₁₉ NO ₅ S:

Calculated: C42.7; H7.56; N5.53; S 12.66;

found: C42.6; H7.49; N 5.75; S 12.38.

The process according to the invention (procedure according to Part A) can also be applied to compounds according to Part D can be applied using the hydrochloride or other salt of a strong one Acid, whereupon the 7-chloro compound obtained is subjected to the further process steps.

E. methyl-6,8-dideoxy-6- (l'-carbobenzoxy-4'-butyl-L-2-pyrrolidine-carboxamido) -l-thio-

D-erythro-a-D-galacto-octopyranoside, free base Z

C ₄ H ₉

+ a-MTL
COOH

PO (III)

C ₄ H ₉

COMTL
(XXIV)

45

To a solution of 6.4 g 4-Butyl-l-carbobenzoxy-L-proline (oil part B in accordance) cooled in 175 ml of distilled acetonitrile at 0 ⁰ C, 3.46 ml of triethylamine and then 3.34 ml of isobutyl chloroformate admitted. The mixture was ^{stirred at 0} ° C. (+ 3 °) for 15 minutes, after which a solution of 6.2 g of a-MTL base according to Part D in 85 ml of water was added; the reaction mixture was stirred at OcC for half an hour and then at 25 ° C for 1 hour. The reaction product was filtered off and dried, giving 4.57 g (37.7%) of methyl-6,8-dideoxy-6- (l'-carbobenzoxy-4'-butyl-L-2-pyrrolidinecarboxamidoVl-thio-D- erythro-aD-galacto-octopyranoside was obtained in the form of the free base. The mother liquors were concentrated in vacuo, whereby a further 4.25 g (35.2%) of product could be obtained. On recrystallization from acetonitrile, methyl-6,8-dideoxy was obtained -6- (l'-carbobenzoxy-4'-butyl-L-2-pyrrolidinecarboxamido) -l-thio-D-erythro-aD-galacto-octopyranoside obtained from melting point 194 to 196 ° C. Further recrystallization from acetonitrile gave an analytically pure sample with a melting point of 195.5 to 200 ° C., [aß ⁵ : + 111 ° (c = 0.98 MeOH).
Analysis for C ₂₆ H ₄₀ N ₂ O ₈ S:
Calculated C57.75, H7.46, N5.13, S5.93;
Found: C, 57.58; H 7.16; N 5.50; S 6.07.

F. Methyl 6,8-dideoxy-6- (4'-butyl-L-2-pyrrolidinecarboxamido) -l-thio-D-erythrou-D-galacto-octopyranoside hydrochloride

• HCl

COMTL V "" 1 / COMTL

J 1 (XXV) C ₄ H _{9 Vy} P (XVI)

A solution of 7.8 g of methyl-o ^ -dideoxy-o-tl'-carbobenzoxy ^ 'rbutyl-L ^ -pyrrolidincarboxamido) -

1 -thio-D-erythro-a-D-galacto-octopyranoside in part E, in 200 ml of methanol was over 2 g of 10% palladium-carbon catalyst at 2.8 g Atmospheres of hydrogen shaken for 17 hours. The catalyst was then filtered off and the solution concentrated in vacuo. The residue was in a mixture of 20 ml of acetone and 20 ml of water dissolved and acidified with 6N hydrochloric acid. When diluting with 4 parts by volume of acetone, methyl-6,8-dideoxy-6- (4'-butyl-L-2-pyrrolidinecarboxamido) - l-thio-D-erythro-a-D-galacto-octopyranoside hydrochloride from which was filtered off and dried. The crystals thus obtained were at 55 ° C in a vacuum dried; Yield 4.7 g, melting point 188 to 194 ° C. The recrystallization from acetone

Analytically pure sample held showed a melting point of 197 to 199 ° C; [a] ² _D ⁵ : 150 ° (water, c = 0.89).

Analysis for C ₁₈ H ₃₄ N ₂ O ₆ S-HCl:
Calculated: C48.80; H7.96; N6.32; S7.24;
found: (corrected for 5.54% water) C48.58; H8.19; N6.04; S7.36.

The material possessed 8% of the antibacterial activity of lincomycin against S. lutea.

If desired, the l'-carbobenzoxy compounds obtainable according to Part E, according to the Process according to the invention (cf. Part A) chlorinated and the resulting 7-chloro compounds under Removal of the 1-carbobenzoxy group and substitution of the proline nitrogen can be implemented further.

G 1. Methyl-6,8-dideoxy-6- (l'-methyl-4'-butyl-L-2-pyrrolidinecarboxamido) -l-thio-D-erythro-a-D-galacto-octopyranoside hydrochloride

• HC1
COMTL

CXXVII)

A solution of 2.0 g of methyl-6,8-dideoxy-6- (4'-butyl-L-2-pyrrolidincarboxamido) -l-thio-D-erythro- a-D-galacto-octopyranoside hydrochloride according to Part F and 2.0 ml of 37% formalin in 150 ml of methanol was over 500 mg of 10% palladium-carbon catalyst shaken at 2.8 atmospheres of hydrogen for 3.5 hours. After filtering off the catalyst and distilling off the solvent in vacuo gave partially crystalline methyl-6,8-dideoxy-6- (l'-methyl-4'-butyl-L-2-pyrrolidinecarboxamido) -lthio-D-erythro-aD-galacto-octopyranoside- hydrochloride, obtained by thin layer chromatography on silica gel using a mixture of ethyl acetate, Acetone and water (8: 4: 1) for elution and a potassium permanganate solution for determination as consisting mainly of 2 materials, namely the cis and trans epimers of Methyl-6,8-dideoxy-6- (l'-methyl-4'-butyl-L-2-pyrrolidinecarboxamido ^ l-thio-D-erythro-a-D-galacto-octopyranoside hydrochloride in a ratio of about 3: 2.

G 2. Separation of the cis and trans forms
by chromatography

The obtained according to Part Gl methyl-6,8-dideoxy-6- (l'-methyl-4'-butyl-L-2-pyrrolidinecarboxamido) -l- thio-D-erythro-a-D-galacto-octopyranoside-hydrochloride were dissolved in a mixture of methanol and methylene chloride (1: 1) and with 1.5 ml of triethylamine offset. To this solution, 7 g of silica gel was added and the solvent was removed in vacuo evaporated. The antibiotic deposited on the silica gel were on top of a chromatographic Abandoned column, the 200 g of silica gel, soaked with a solvent mixture of ethyl acetate, acetone

• HCl
COMTL

C ₄ H.

4 ^Π 9

(XXVIII)

and water in a ratio of 8: 4: 1. The column was developed by eluting with the same Solvent system, collecting 20 ml portions. By thin-layer chromatographic Examination of the individual fractions it was found that fractions 31 to 38 (310 mg) consisted of essentially pure trans epimers, fractions 49 to 74 (32 mg) of essentially pure cis epimers, and fractions 39 to 48 from a mixture of epimers. The latter could separated by repeated chromatography. The individual epimers were in little Drops of dilute hydrochloric acid dissolved, whereupon the hydrochloride was precipitated by adding acetone became. In this way, 50 mg of methyl-6,8-dideoxy-6- (trans-l'-methyl-4'-butyl-L-2-pyrroli- dincarboxamido ^ l-thio-D-erythro-oc-D-galacto-octopyranoside hydrochloride from melting point 135 to 137 ° C and about 150 ml of methyl-6,8-dideoxy-6- (cis-l'-methyl-4'-butyl-L-2-pyrrolidinecarboxamido) -l-thio- D-erythro-oc-D-galacto-octopyranoside hydrochloride from softening point 105 ° C, melting point 175 to 185 ° C.

The trans epimer melted at 139 bis after recrystallization from the same solvent 141 ° C

Analysis for C ₁₉ H ₃₆ N ₂ O ₆ S · HCl:

Calculated: C, 49.93; H 8.16; N 6.13; S 7.02;

found: (corrected for 4.07% H ₂ O): C48.81; H8.54; N6.49; S6.67.

From the cis epimers gave a product having a softening point 108 ° C, melting point 189 ⁰ C (solvate) in the recrystallization,

Analysis: Found (corrected for 4.95% water): C50.27 .; H9.00; N6.05; S6.65i- _; ν. ν.

The trans epimer was about 2.2 times as active as lincomycin (against S. lutea), about twice as active in the nutrient broth dilution test, and 2.5 times as active in mice infected with S. aureus.

The cis epimer was about ¹ _1/2 to 1/3 as active as the trans epimer and about the same as lincomycin.

H1. Methyl-6,8-dideoxy-6- (1'-ethyl-4'-butyl-L-2-pyrrolidinecarboxamido) -1 -thio-D-erythro-a-D-galacto-octo pyranosid- ' hydrochloride

A mixture of 2.0 g of methyl 6,8-deoxy-6- (4'-butyl-L-2-pyrrolidinecarboxamido) -l-thio-D-erythro-a-D-galacto-octopyranoside hydrochloride according to Part F, 1.5 ml of acetaldehyde and 150 mg of 10% palladium-carbon in 150 ml of methanol was shaken at 2.5 atmospheres of hydrogen pressure for 5.5 hours. The catalyst was filtered off and a residue was obtained, consisting mainly of the cis and trans epimers of methyl-6,8-dideoxy-6- (l'-ethyl-4'-butyl-L-2-pyrrolidinecarboxamido) -l-thio-D-erythro-a-D- galacto-octopyranoside hydrochloride.

H 2. Separation of the epimers

25 bar. However, it is desirable to keep the trans isomer content high, since this isomer is the more pharmacologically active form.

When carrying out the process, epimer mixtures with a ratio of trans to cis epimers of 3: 1 to 1: 5 can be obtained.

The physical characteristics of some further compounds of the formula prepared according to the invention IB are compiled in the following table I:

Table I.

Physical characteristics for hydrochlorides of compounds prepared according to the invention of the general Formula IB

Note on nomenclature: Clindamycin is 7 (S) -chloro-7-deoxy-lincomycin or methyl-7-chloro-6,7,8-trideoxy-6- (r-methyl-4'-trans-propyl-L-2 -pyrrolidincarboxamido) -l-thio-L-threo-aD-galacto-octopyranoside

A) l'-demethyl derivatives of clindamycin

The aforementioned epimer mixture (2 g) was, as described under G 2, chromatographed on 200 g of silica gel, using a solvent for elution

system of ethyl acetate, acetone and water (8: 4: 1) used. Fractions 33 to 42 passed pure trans-epimers (thin-layer chromatography- ^

phie) and were united; fractions 49 and 64 consisted of essentially pure cis-epimers, they were also united. Fractions 43 to 48 consisted of a mixture of epimers, which by repeated chromatography could be separated. Each of the epimers was in a few Drops of dilute hydrochloric acid dissolved, and the crystalline hydrochloride was diluted with a large volume of ether precipitated.

The fraction of crude trans-epimers weighed c

415 mg; 340 mg (15.4%) of crystalline were obtained therefrom Methyl-6,8-dideoxy-6- (trans-l'-ethyl-4'-butyl-L-2-pyrrolidine-carboxamido) -l-thio-D-erythro-a-45 ■ D-galacto-octopyranoside hydrochloride of melting point 144 to 151 ° C. When recrystallizing from dilute acetone, the melting point rose to 148 bis

The fraction of the cis-epimer weighed 645 mg and gave 300 mg (14.1%) of crystalline methyl-6,8-

dideoxy-6- (cis-l'-ethyW-butyl-L ^ -pyrrolidinecarboxamido) -l-thio-D-erythro-a-D-galacto-octopyranoside hydrochloride with a melting point of 135 ° to 139 ° C. Recrystallization from dilute acetone gave Crystals with a melting point of 134 to 138 ° C.

The trans-epimer showed the 1- to 1.2-fold activity of lincomycin against S. lutea, the 2 to 4-fold Activity of lincomycin against gram-positive organisms and at least 8 times the activity of the 60 " Lincomycins against gram-negative organisms. In the mouse test against S. aureus this was trans-epimer about twice as active as lincomycin; the ice- '

Epimers showed about * / ₂ times the activity of the trans-epimers. 65

The separation of cis and trans isomers is not absolutely necessary, since the epimer mixture of the 7-chloro derivatives can also be used as such'-DemethyW-trans-clindamycin hydrochloride [R = CH ₃ , HR ₁ = trans-C ₃ H ₇ , R ₃ = H], crystals m.p. = 229-231 ° C;

1 '-DemethyW-cis-clindamycin hydrochloride [R = CH ₃₅ HR ₁ = CiS-C ₃ H ₇₅ R ₃ = H],

Mp = 229-232 ° C (dec.), [Ate ⁵ + 151 ° (H ₂ O).

1 '-DemethyW-cis / trans-clindamycin hydrochloride

[R = CH ₃ , HR ₁ = cis / trans -C ₃ H ₇ , R ₃ = H],

Mp = 228-234 ⁰ C, [ate ⁵ + 159 ° (H ₂ O).

1 '-DemethyW-depropyW-cis / trans-n-butylclindamycin hydrochloride

[R = CH ₃ , HR ₁ = cis / trans-nC ₄ H ₉ , R ₃ = H], mp = 207 to 209 ° C (dec.),

[ate ⁵ + 134 ° (methanol);

1 '-DemethyW-depropyW-trans-n-pentylclindamycin hydrochloride

[R = CH ₃ , HR ₁ = trans-n-CsHjj, R ₃ = H], melting point = 211 to 212 ° C (dec.)

1 '-DemethyW-depropyW-cis-n-pentylclindamycin hydrochloride

[R = CH ₃₅ HR ₁ = CiS-UC ₅ H ₁₁₅ R ₃ = H], melting point = 217 to 219 ° C (dec.);

1 '-DemethyW-depropyW-cis / trans ^' - pentylclindamycin hydrochloride

[R = CH ₃ , HR ₁ = cis / trans-CsH! ,, R ₃ = H],

M.p. = 222-223 ° C (dec.); [ate ⁵ + 139 ° (H ₂ O)

1 '-DemethyW-depropyW-cis-trans-isopentylclindamycin hydrochloride

[R = CH ₃ , HR ₁ = trans-iso-C ₅ H _n , R ₃ = H],

Mp = 125-145 ⁰ C (dec.).

1 '-DemethyM-depropyW-cis / trans-hexyl-

clindamycin hydrochloride

[R = CH ₃ , HR ₁ = cis / trans-C ₆ H ₁₃ , R ₃ = H],

Mp = 219 to 221 ° C; ;% _,;

1 '-DemethyM'-depropyM'-cis / trans-n-octyl; - ί ^s clindamycin hydrochloride "

[R = CH ₃ , HR ₁ = cis / trans -nC ₈ H ₁₇ , R ₃ = H] ₅ mp = 201-203 ° C (dec.);

409 539/357

11. r-DemcthyW-depiOpyW-cis / trans-ethylclindamycin hydrochloride

[R = CH ₃ , HR ₁ = CiSZtHUiS-C ₂ H ₅ , R ₃ = H] mp = 240 to 242 ° C;

12. Clindamycin hydrochloride [7 (S) -chloro-7-deoxy-5 lincomycin hydrochloride; see example 1] [R = CH ₃ , HR ₁ = trans-C ₃ H ₇ , R ₃ = CH ₃ ], crystals, [ate ⁵ + 130 ° (c = 0.9858 g / 100 ml H ₂ O) ;

13, 7 (R) -chloro-7-deoxy-lincomycin hydrochloride [ate ⁵ + 122 ° (H ₂ O);

14. 4'-Depropyl-4'-trans-ethyl-clindamycin hydrochloride [7 (S) -chloro-7-deoxy- lincomycin B hydrochloride]

[R = CH ₃₁ HR ₁ = IHmS-CH ₅₁ R ₃ = CH ₃ ] _{,, 5}

[a ⁵ + 149 ° (H ₂ O);

15. 4'-Depropyl-4'-lrans-pentyl-clindamycin hydrochloride

[R = CH ₃ , HR ₁ = InilIS-C ₅ H ₁₁ , R ₃ = CH ₃ ], [α ⁵ + 125 ° (H ₂ O);

16. 4'-Depropyl-4'-trans -hexyl-clindamycin hydrochloride

[R = CH ₃ , HR ₁ = IHUiS-C ₆ H ₁₃ , R ₃ = CH ₃ ],

[a ⁵ + 125 ° (H ₂ O); _25th

17. 1-Demethyl-1-ethyl-clindamycin hydrochloride [7-ChloI · -7-deoxy-lincomycin-C hydrochloride], [R = C ₂ H ₅ , HR ₁ = tnms-C ₃ H ₇ , R ₃ = CH ₃ ], [α ⁵ + 136 ° (H ₂ O);

18.! ', L-dimethyl-1M-diethyl-clindamycin hydrochloride

[R = CH ₅ , HR ₁ = IHUiS-C ₃ H ₇ , R ₃ = CH ₅ ], [a] _D + 151 ° C;

The IR and NMR spectra were consistent with the structure _35.

19. 1'-Demethyl-1'-ethyl-clindamycin hydrochloride [7 (S) -chloro-7-deoxy-N-ethyl-lincomycin-D-hydrochloride]

[R = CH ₃ . HR ₁ = trans -C ₃ H ₅ , R ₃ = CH,], 4 °

[a ⁵ + 133 ° (H ₂ O);

20. 1 '-Demethyl-1' -äthyW-depropyM'-cis-butylclindamycin hydrochloride

[R = CH ₃ , HR ₁ = CiS-C ₄ H ₉ , R ₃ = CH ₅ ], ₄₅

[a ⁵ + 106 ° (H ₂ O);

21. 1 '-Demethyl-1'-ethyM'-depropyl ^ '- transbutyl-clindamycin hydrochloride [R = CH ₃ , HR ₁ = IHUiS-C ₄ H ₉ , R ₃ = C ₂ H ₅ ]. Elemental analysis: (values calculated in brackets - ⁵ ° for C ₂₀ H ₃₈ Cl ₂ N ₂ O ₅ S)
C%: 48.38 (49.07); H%: 8.03 (7.83); N%: 5.56 (5.72); S%: 6.43 (6.55); Cl%: 15.06 (14.49); H ₂ O%: 3.02.

22. 1 '-Demethyl-1' -ethyW-depropyl ^ '- transhexyl-clindamycin hydrochloride [R = CH ₃ , HR ₁ = trans-C ₆ H ₁₃ , R ₃ = C ₂ H ₅ ], [ate ⁵ + 124 ° (H ₂ O);

23. 1 '-Demethyl-1'-isopropyl-4'-depropyI-4'-cis / trans-penlyl-clindamycin hydrochloride [R = CH ₃ , HR ₁ = CiSArUnS-C ₅ H ₁₁ , R ₃ = ISO- C ₃ H ₅ ] Mp = 77-80 ° C.

The values found in the elemental analysis 65 agreed with all of the aforementioned compounds correspond well to the calculated values.

If lincomycin according to Part Ades Example 5 by

55

60 replaces the corresponding δ-amino-o ^ -dideoxy-l-thio-D-erythro- or L-threo-aD-galacto-octopyranoside, compounds corresponding to the general formula I with Ac = hydrogen, where R is the there has mentioned meaning. These can be acylated according to the procedure of Example 4 to form the corresponding 7-chloro-7-deoxylincomycin derivatives of the formula I.

Example 5

Methyl-7-chloro-6,7,8-trideoxy-6- (trans-4-butyI-

L-2-pyrrolidincarboxamido) -1 -thio-L-threo-

α-D-galacto-octopyranoside

and its 4-cis isomer

NS,

OH

Part A

A suspension of 116 mg of methyl 6,8-dideoxy-6- (trans-4-butyl-L-2-pyrrolidinecarboxamido) -l-thio-D-erythro-aD-galacto-octopyranoside as a free base in 3 ecm carbon tetrachloride and 0.7 cc of thionyl chloride was stirred at 25 ° C until a clear solution is obtained (about 15 minutes), and then allowed to stand for 2 hours at 25 ⁰ C. The reaction mixture was then heated for 2 hours at Rückfiußtemperatur and evaporated to dryness under vacuum to give a yellow solid which was dried for 18 Stunder, under vacuum at 40 ⁰ C. The product was then dissolved in about 15 ecm warm ethanol, made basic with sodium hydroxide, as in Example 1, and diluted with water to 300 ecm. The water solution was extracted five times with 100 ecm of ether each time. The ether extracts were combined, dried over magnesium sulfate, filtered, saturated with hydrogen chloride gas and the ether stripped off. Methyl 7-chloro-6,7,8-trideoxy-6- (trans-4-butyl-L-2-pyrrolidinecarboxamido) -l-thio-L-threo-aD-galacto-octopyranoside hydrochloride was obtained as a red-brown amorphous Solid with at least eight times the activity of lincomycin.

If the cis-epimer is used, methyl-7-chloro-6,7,8-tridioxy-6- (cis-4-butyl-L-2-pyrrolidine-carboxamido) -l-thio-L-threo- aD-galactooctopyranoside hydrochloride, which has the same antibacterial spectrum.

The cis and trans epimers used from starting substances in the above example were produced and separated as follows:

part B

Methyl 6,8-dideoxy-6- (4'-cis / trans -butyl-L-2-pyrro-Iidincai "boxamido) -l-thio-D-cry thro-a-D-galacto-

Octopyranoside hydrochloride was obtained by following the procedure of Parts B through F of Example 4.

Optionally, the l'-carbobenzoxy compound, prepared according to Part E of Example 4, according to the method described in Part A of this example is chlorinated, and the resulting 7-chloro compound the 1'-carbobenzoxy group can be removed in a manner known per se by hydrogenation.

Part C ίο

Separation of the cis and trans forms by
Chromatography

The methyl-6,8-dideoxy-6- (4-cis / trans-butyl-L-2-pyrrolidincarboxamido ^ l-thio-D-erythro-a-D-galacto- Octopyranoside hydrochloride (from Part B) was made in a mixture of methanol and methylene chloride (1: 1) dissolved and treated with 1.5 ecm of triethylamine. 7 g of silica gel were added to this solution and the solvent was evaporated off in vacuo, with the antibiotic deposited on the silica gel. The latter was packed onto a 200 g silica gel Given a chromatography column containing one made of ethyl acetate, acetone and water in a ratio of 8: 4: 1 existing solvent mixture had been filled. The column was eluted with the same solvent developed, with fractions of 20 ecm each were collected. The ; Fractions were checked by thin layer chromatography. The faster moving ones active fractions were essentially pure trans epimers, which were slower moving active fractions were predominantly pure cis epimers. Each epimer was dissolved in a few drops of dilute hydrochloric acid, and the hydrochloride through Addition of acetone precipitated. In this way, methyl 6,8-dideoxy-6- (trans-4-butyl-L-2-pyrroljdincarboxamido) -l-thio-D-erythro-a-D-galacto-octopyranoside hydrochloride was obtained and methyl 6,8-dideoxy-6- (cis-4-butyl-L-2-pyrrolidinecarboxamido) -l-thio-D-erythro-a-D-galacto-octopyranoside hydrochloride.

Example 6

Methyl-y-chloro-oJ ^ -trideoxy-o-itrans-l-methyl ^ - propyl-L-2-pyrrolidinecarboxamido) -l-thio-D-erythroa-D-galacto-octopyranoside- [7-chloro-7-deoxy-epilincomyein].

A. Chlorination of epilincomycin

55

60

65

0.85 g of 7-epilincomycin hydrochloride were in 17 ml Suspended carbon tetrachloride. Then 4.5 ml of thionyl chloride were added and the reaction mixture was stirred for 15 minutes at 25 ° C. The solid dissolved to give a clear, colorless one Solution. The reaction mixture was then refluxed for 2 hours, cooled to 25 ° C and evaporated in vacuo to a yellow solid residue. This product was dissolved in 10 ml of ethanol, made basic with 0.1 η sodium hydroxide, diluted with 500 ml of water and four times with 50 ml each Chloroform extracted. The combined chloroform extracts were washed twice with 20 ml of saturated sodium chloride solution each time washed, filtered and evaporated in vacuo. The solid residue was slurried with 500 ml of ether, then filtered and the filtrate passed in hydrogen chloride gas. The resulting precipitate was collected in 3 ml Dissolved ethanol and reprecipitated by adding ether.

The solid was collected and dried, giving in 30% yield (270 mg) 7-epichloro-7-deoxylincomycin obtained, which had about 2 to 3 times the activity of lincomycin. In thin-layer chromatography on silica gel (methanol: chloroform system, volume ratio 1: 6), a spot with an Rf value of 0.44 was obtained, the Rf value for 7-chloro-7-deoxylincomycin is 0.52.

Epilincomycin was gradually obtained from lincomycin by the following procedure:

B. 3,4-0-isopropylidene-lincomycin

A solution of 9.8 g of lincomycin in 150 ml of acetone is added to a solution of 9.8 g of p-toluenesulfonic acid monohydrate in 100 ml of acetone while stirring vigorously and excluding moisture. The mixture is stirred at room temperature for about 1 hour, after which 100 ml of anhydrous ether are added; stirring is continued in an ice bath for 1/2 hour. The mixture is then filtered and the solid is dried in vacuo at 50 ° C; Yield 13.35 g (85.5%) of 3,4-O-isopropylidene lincomycin-p-toluenesulfonate. A further 1.15 g (7.4%) can be obtained from the mother liquors by adding 350 ml of anhydrous ether and cooling the solution for one hour. The 14.5 g thus obtained are suspended in 200 ml of ether and vigorously shaken with 125 ml of 5% potassium bicarbonate solution. The aqueous layer is back-extracted twice with 100 ml of ether each time. The ether extracts are washed with 50 ml of saturated sodium chloride solution and then filtered through anhydrous sodium sulfate. The ether is distilled off in vacuo, 7.9 g (73.1%) of 3,4-0-isopropylidene lincomycin remaining, which is dissolved in 25 ml of ethyl acetate, whereupon it is concentrated to 10 to 15 ml. The concentrate is allowed to stand at room temperature for several hours and then refrigerated overnight. The crystals are filtered off from the solution and washed with a little cold ethyl acetate; Yield 4.55 g (42.2%) of 3,4-O-isopropylidene lincomyein, melting point 126 to 128 ° C; optical rotation [α] ?, ⁵ : 101 to 102 ° (c = 1, methylene chloride).

C. 7-Dehydro-3,4-0-isopropylidene lincomycin

To a solution of 6 g (0.0135 mol) of isopropylidene lincomycin in 75 ml of pyridine, 12 g (excess) Chromium oxide added. The solution warms

around 20 ° C. After 1 hour, the mixture was added to a solution containing 250 ml of ethyl ether and Ethyl acetate contained. The mixture was then filtered and concentrated to a syrup (8.4 g). This syrup was in a 500 pass countercurrent distribution system using the solvent system Water: ethyl acetate: ethanol: cyclohexane (1: 1: 1: 1) distributed.

7-Dehydro-3,4-O-isopropylidene lincomycin was isolated from tubes 330-380, K = 2.45.

Analysis for C ₃₁ H ₃₆ N ₇ O ₆ S:

Calculated: C, 56.72; H 8.16; N 6.30; S 7.21.

Found: C, 56.37; H 7.62; N 6.51; S 6.84.

D. 3,4-0-Isopropylidene-epilincomycin

To 1.6 g of Craig's pure 7-dehydro-3.4-O-isopropylidene lincomycin 400 mg of sodium borohydride in 75 ml of methanol were added. After 1.5 hours it was the solution evaporated to dryness on a drum evaporator. 25 ml of water were added to the residue, whereupon it was extracted three times with 25 ml of methylene chloride each time. The extract was made with 15 ml of water back washed, then dried over magnesium chloride and evaporated to dryness. The residue of 1.4 g was in a countercurrent distribution unit with 500 transitions distributed using a solvent system composed of water: ethyl acetate: Ethanol: Cyclohexane (1: 1: 1: 1), and there was a single peak corresponding to the theoretical value, observed at K = 1.05. The material from tubes 240-280 was isolated in the form of a syrup.

Analysis for C ₂ ! H ₃₈ N ₇ O ₆ S:

Calculated: C, 56.47; H ~ 8.58; N 6.27; S 7.18.
• Found: C, 56.24; H 8.54; N 6.13; S 7.01.

It was determined by thin layer chromatography that this material was composed of two substances, viz the 3,4-O-isopropylidene-lincomycin and the 3,4-O-isopropylidene-epilincomycin, which wandered a little slower.

D. Epilincomycin

45

The syrup of Part C was kept in a solution containing 60 ml 0.25 η-hydrochloric acid and 40 ml of ethanol. Then the mixture was kept at 0 ° C for 4 days. It was then neutralized with sodium carbonate, concentrated to 25 ml and extracted with chloroform. The extract was washed with a little water and dried over magnesium sulfate and then used for Evaporated to dryness. Thin-layer chromatography of the residue revealed two substances both of which were active against S. lutea. The residue was passed on to a synthetic Silicate of the type described in U.S. Patent 2,393,625 gradually filled column (35 χ 1.8 cm) eluted, the solvent continuously from 100% of a technical hexane mixture to 100% Acetone passed over. The total volume of solvent was 5000 ml. In this way, the two epimeric compounds separated.

Fraction I: tubes 53 to 65 (fractions of 40 ml each) epilincomycin.

Test value: 450 mcg / ml.

Analysis for C ₁₈ H ₃₄ N ₂ O ₆ S:
Calculated: C, 50.92; H 8.55; N 6.60; S 7.56.
Found: C, 50.19; H 7.91; N 6.05; S 6.42.
Fraction II: tubes 73-104 lincomycin.
Test value: 950 mcg / ml.

Example 7
7-chloro-7-deoxylincomycin hydrochloride

10 g (0.0226 mol) of lincomycin hydrochloride, 200 ml of carbon tetrachloride and 10 ml of SOCl ₂ were refluxed with stirring for 4 hours. The reaction mixture was then cooled to 25 ° C. and filtered. The yellow solid was dried in vacuo and then dissolved in about 10 ml of boiling ethanol. Ethyl acetate was then added until the onset of cloudiness, whereupon the solution was allowed to cool. In this way, crystalline 7-chloro-7-deoxylincomycin hydrochloride was obtained in a yield of about 43%.

Example 8

l'-demethyl-l-ethyW-depropyl ^ '- n-hexyl-7 (S) -chlor-7-deoxy-lincomycin

nC ₆ H

₆ H _n

SCH ₃

OH

OSCl ₇

C-NH

nC ₆ H _u O HO

NS,

OH

1.4 ml of thionyl chloride were added to a stirred suspension of 1.4 g of methyl N- (1'-ethyM'-n-hexyl-L-.prolyO-thioline cosaminide hydrochloride (see formula on the left above) in 28 ml of CCl ₄ , Refluxed for 2 hours and then evaporated to dryness in vacuo, 100 ml of chloroform was added and then evaporated in vacuo. The chloroform addition and evaporation were repeated two more times to achieve complete removal of the thionyl chloride. The solid residue became dissolved in 5 ml of ethanol, cooled in an ice bath, and the pH was adjusted to 10 by adding 1N NaOH, then 200 ml of water was added and the basic solution became

extracted well with chloroform. The extracts were evaporated and dried, leaving 1.0 g of crude product which were obtained on silica gel using a mixture of methanol and chloroform was purified by chromatography in a ratio of 1: 6 as the eluent. The the material you want containing fractions (determined by thin layer chromatography) were combined and evaporated.

The 4'-trans compound has an optical rotation of [aß ⁵ = + 124 ° (H ₂ O).

Example 9

7- (S) -chloro-7-deoxy-lincomycin
with isolation of the intermediates

in-ß ^ - O-cyclic

sulfite

CH,

Cl

NS,

O = S

35

systems chromatographed again over 600 g of silica gel. After collecting 700 ml of the first runnings 3 to 9 these were evaporated to dryness and again using 50 ml portions of the same solvent system via silica gel chromatography. After a preliminary run of 700 ml Fractions 3 to 9 were collected and evaporated to dryness, leaving 7- (S) -chloro-7-deoxylincomycin-3,4-O-cyclic Sulphite was obtained, which has the following characteristics:

[ate ⁵ + 171 ° (C, 0.802, CHCl ₃ ).

Molecular weight 471 (mass spectrometer)
472 (calc.)

Analysis for (C ₁₈ H ₃ ! ₂₆₂

• Calculated: C 45.89%; H 6.63%; N 5.95%; S13.61%; Cl 7.53%;

found: C 46.02%; H 6.54%; N 5.99%; S 13.20%; Cl 7.59%.

If one considers fractions 3 to 8 of the first chromatographic separation mentioned above collects and evaporates to dryness, bis- [7 (S) -chlor-7-deoxylincomycin-3,4-O-cyclic is obtained SuI-fit] sulfite of the formula below, which has a melting point of 184 to 186 ° C.

Analysis for (C ₃₆ H ₆₀ Cl ₂ N ₄ O ₁₃ S ₅ ):

Calculated: C 43.76%; H 6.12%; N 5.67%; Cl 7.18%; S 16.23%;

found: C 39.93%; H 5.71%; N 5.41%; Cl 7.48%; S 16.00%.

Bis- [7 (S) -chloro-7-deoxylincomycin-3,4-O-cyclic
Sulfite] sulfite

A suspension of 221.0 g (0.5 mol) of lincomycin hydrochloride in 5 liters of carbon tetrachloride was stirred well under nitrogen at 25 ⁰ C. Then 900 ml of thionyl chloride were added all at once, followed by stirring for a further 2 hours. During this time the solid dissolved and a clear solution was obtained. The reaction mixture was refluxed for 2 hours after which the heat was removed and nitrogen was bubbled into the amber solution until the flask temperature dropped to 25 ° C. About 4 liters of the liquid was then removed by vacuum distillation at a pot temperature of less than 35 ° C. The yellow dye which separated out during the distillation was collected and dried. The yellow solid was chromatographed over 3 kg of silica gel using 250 ml portions of methanol and chloroform (volume ratio 1: 9). After a forerun of 3 liters, fractions 9 to 24 were collected, evaporated to dryness and, using 50 ml parts of the same solvent,

O = S

SCH ₃

B: The 7- (S) -chloro-7-deoxy-3,4-O-cyclic compounds thus obtained Sulphides result from alkaline hydrolysis (neutralization with NaOH and adjusting to a pH of about 11) that described in Example 1 7 (S) -chloro-7-deoxy-lincomycin.

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Claims (1)

Claim: Process for the preparation of 7-chloro-7-deoxylincomycin and epi-lincomycin and their derivatives and analogs of the general formula I (I) OH 20th