NL8300369A - 3-Enol ethers of pregneneones prepn - from the 4-en-3-ones and triethyl-ortho-acetate in a mixed solvent - Google Patents

Abstract

Steroids of formula: (where R is H, OH, 1-6C alkoxy or 1-6C alkanoyl oxy, R2 is H, OH, or 1-6C alkanoyloxy, R2 is H, alpha-CH3 or beta-CH3, X is H, F, Cl or Br) and their 16 alpha, 17 alpha-acetals and -ketals derived from R4COR4 wherein R4 and R5 are each 1-4 C hydrocarbon radicals are converted into 3-enol ethyl ethers by reaction with triethyl orthoacetate in the presence of a catalytic amt. of a strong acid in a solvent consisting essentially of about 40 wt % or more ethanol and about 60 wt % or less of a compatible oxygenated hydrocarbon liq. The process is simpler than similar known processes in that (I) dehydration of the the 9 (11) position is substantially completely eliminated, so there is no need to oxidized the 11 -ol to an 11 -one, and (II) a 17 alpha, 21 -dihydroxy side chain does not require protection. Also yields are increased and inexpensive solvents may be used. The 3-enol ethyl ethers are chiefly of use in the prepn. of therapeutically active 6-halo-DELTA1,4,6-pregnation-3-ones.

Description

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Process for the preparation of 3-enol ethers of 11 (3-hydroxy-A-pregnene-3-ones and derivatives thereof).

The invention relates to a process for the preparation of 3-enol ethers of 11g-hydroxy-A-impregn-3-ones and derivatives thereof. In particular, the invention relates to a process for the preparation of 3-enol-4-ethers of 3-oxo-A-11-hydroxysteroid compounds by reacting the 3-oxo-Δ ^ -11-hydroxysteroid with triethyl orthoacetate in presence of a significant amount of ethanol. This reaction contributes to a new process for the preparation of 6-halogen-A ^ "^ pregnadienes and Δ ^" ^ "^ pregnatriens, especially.

10 without the 6-chloro-A * * -pregnatriene-11,17a.21-triol-3,20-diones and the corresponding 21-acetates.

In the preparation of the active steroid compounds for use as e.g. anti-inflammatory drugs, it is often necessary to start from an easily obtainable compound and then carry out a significant number of steps, these steps being based on reacting a group of the compound to form a protecting group and then reacting another group of the compound as desired. This method often requires a large series of stages 20 to obtain the desired product, and in each stage there is a certain loss of yield, which, taken over the different stages, can add up to a significant and costly loss of yield for the entire process . Therefore, the steroid chemistry researchers are constantly working to develop effective reaction schemes to increase the overall yield by decreasing the number of steps required for a reaction sequence, by increasing the yield for a given stage or both. The overall yield can be improved either by providing a process in which virtually all of the starting material is reacted to form the desired product, or side reactions are kept as low as possible.

An important step in many reaction-4 6 schemes for the preparation of 6-halogen-A * -pregnadiene or 14 6 Δ '* -pregnatriene is based on the reaction of a "cortisol-like" compound with a 3- οχο-Δ group in an enol ether (i.e.

The formation of a 3-alkoxy-A 'intermediate) by reacting the 3-keto-4Δ steroid with a short chain alkyl orthoformate in a suitable solvent, such as dioxane in the presence of a sodium catalyst, such as p -toluenesulfonic acid, When starting from an readily available compound such as cortisol (hydrocortisone; 1Τβ, 17a, 21-trihydroxy-3.20-dioxopregn-4-one), which contains a reactive hydroxy group in the 21- and Ιΐβ-position, it used to be however, it has already been shown that it is preferable to first react the cortisol (represented by formula 1) with formaldehyde and methylene chloride in hydrochloric acid to form a dimethylenedioxo (BMD) compound as represented by formula 2 in scheme A. See e.g. U.S. patents 2,888,456 and 2,888,457.

In order to prevent the formation of a Δ ^ ^ derivative 20 during the subsequent reaction with the short chain alkyl orthoformate in acid by dehydration of the OH at the 113 position and the H at the 9 position, the 11β-0Η group is first oxidized with e.g. chromic acid in sulfuric acid in dimethylformamide (DMF) according to scheme B.

The compound of formula 3 is then treated with the short chain alkyl orthoformate and acid to form the desired enol ether of formula 4 which is then further treated as required according to scheme C, wherein R is a short chain alkyl group.

In U.S. Pat. No. 3,082,224 it has been proposed to solve the dehydration problem by reacting a cortisol or a cortisol 21 ether with a short chain alkyl orthoformate in a solvent, consisting exclusively of the corresponding short chain alkanol and an acid catalyst. Using this method, it is believed that the dehydration can be reduced to less than 10% and the 3-enol ether can be obtained 8300369

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3 * in. a yield of 65-90%.

Another patent that discusses the formation of the intermediate 3-enol ether of the above type is U.S. Patent 3,087,927. In this series of 5 reactions, the starting material was e.g. 16-hydroxycortisole or 16-hydroxycortisone. This patent discloses that these materials can be reacted in the presence of a mineral acid with an ortho ester of the formula R ^ C (OR ^) ^ 3 wherein R ^ is hydrogen or a short chain alkyl group (with 1- 3 carbon atoms) and R 1 is a short chain alkyl group, such as a methyl or ethyl group, whereby a reaction of formula 5 is obtained as reaction product. More specifically, the examples show the reaction performed in dioxane with a small amount of methanol and sulfuric acid with trimethyl orthoformate. The description of this patent does not mention the dehydration problem discussed in U.S. Pat. No. 3,082,224.

Thus, the prior art assumes that 11-hydroxy-A-pregnene-3-ones can be reacted to form the corresponding enol ether using: (1) trialkyl formate, using a major amount of a solvent, such as dioxane or a minor amount of the corresponding short chain alkanol (ie trimethyl orthoformate with methanol or triethyl orthoformate with ethanol), (2) using triethyl orthoacetate with a major amount of a solvent, such as dioxane with a minor amount of ethanol, or, (3) using triethyl orthoformate with ethanol as the sole solvent.

In either case, an acidic catalyst is used to run the reaction at the desired rate. It has been found that in the first case the main product is the dehydration product, in the second the reactants do not react and in the third case there is some dehydration between 11th and 9th place and the reaction does not complete. Therefore, in all of the reactions known from the prior art, the yields of the desired enol ether are low, and in a long series of steps this yield is naturally transferred and leads to a reduction in the total production of the desired end product.

We have now found that by using the method of the invention to form a 8300369 1 »

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The following advantages are obtained from 3-enolebher from a 3-οχο-Δ-113-hydroxysteroid: 1) Dehydraterir.g. in the 0 (11) position is obtained almost free of charge. completely avoided; 2) According to T) there is no need to first oxidize the 11-hydroxy green to one-oxo group. reasons for protection; 3) The yield of the enol ether is reduced (in part due to 1 and 2 above, and also in part due to the tendency of the reaction of the present invention to proceed or to complete) · * H) Cheap oxidized hydrocarbon auxiliary solvents such as glyms can be used in conjunction with ethanol; 5) When reacting steroids with 15 17ct, 21-hydroxy groups, it is not necessary to protect these groups via BMD or other methods; and 6) The above 5 advantages alien contribute to a simpler solution than hitherto known in the art.

The main object of the invention is to provide a preparation for the preparation of 3-enol ethyl ethers, which are useful as intermediates for the preparation of therapeutically sold 6-halogen-1 1 * 1 Δ 1 5 -Dregnatriene-3 -ons. It is also an object of the invention to provide a comparison

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provider. for the preparation of o-haloene-A - • Dregren-3-ores, which are also useful as intermediates for the preparation of these 6-halo-A-2, -saturatriene- 3-ones. It is also an object of the invention to provide a particularly effective total solution for the preparation of 6-halogen-A-3-pregnadiene-3-ones and the 6-halogen-A * 5'-pregnatriene.

. . 3-ones.

In the first place, the invention relates to a preparation for the preparation of 3-enol ethers of 11S-hydroxy-A-impregnate-3-ones and derivatives thereof, characterized in that a compound of the formula 6 is used, where R is hydrogen or an OH, OR ^ or 00 (0) 3 ^ group, R ^ is hydrogen or a group OH or 0C (0) F ^, hydrogen or an n- or? -nethyl green, a short chain alkyl group with 1-6 carbon atoms. or a short chain alkester is just 1-6 carbon tones, 8300369

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.... 5 ....

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* * a short chain alkyl group is just 1-6 carbon atoms, X is hydrogen, fluorine, chlorine or bromine and and R0 tezanes can form a group of formula 7, sail in and R, _ independently a volatile group with 1-it carbon atoms are reacted with triethylethoroacetate in the presence of a catalytic amount of a strong acid in an OD solvent which is at least AO sew. or more consisting of ethanol and of about 60% or less of a compatible oxidized liquid hydrocarbon. Preferably, the solvent is a 50/50 mixture of ethanol and glyme and the catalyst is a strong organic acid such as 10-p-toluenesulfonic acid or trifluoroacetic acid. The process is particularly useful for cortisol and cortisol-21-alkyl esters, such as the 21-acetate.

The 3-enol ether obtained is then halogenated, preferably chlorinated, to form the corresponding oS-halogen-Δ-pregnene-3-one, which in turn is treated on a 6-halogen-3-enol ether which is then set in a 6-halogen-Al 1 ^ 6 (o? Λ 1 5) -pregnadiene (or -triene) -3-one as discussed below.

The formation of the 3-enol ether It is important to use triethyl-chloroacetate as a reagent in the process according to the invention. Triethyl ortho-20 acetate is preferred over the corresponding triethyl ortho-forniate. "reed ethyl orthoacetate is represented by the formula: CH.C (OCK.CH-) ,, while triethyl orthoforate in the general is ^ J C. J i represented by the formula:

The chenisne, such as the preparation and the general reactions of the aliphatic orthoesters, are discussed in the book "The Chemistry of Aliphatic Orthoesters", An. Chen. Soc. Monograph by H.W. Mail, publ. Rienhold. Generally, the triethyl orthoacetate can be prepared by various methods, the two most popular of which are indicated by the two comparatives shown in Scheme D.

3D. " Further preparation vir.dt nen on biz. kQ of the above monograph. The methods of preparation used in the reagents of the first equations of scheme D are found in an article 1 in J.A.C.3. 5C_, biz, 516 (1928) to P. Sah.

Although theoretically the amount of triethyl-35 orthoacetate needed to form the 3-enol ether by reaction with the 3-oxo-A ** - 3 teroi & e 1 nol orthoacetate hedraate each mole steroid, 83 \ 8300369 * · "6, it appears, because of the special nature of the reaction. that at least 2 moles of triethyl orthoacetate per mole of steroid are required for the reaction to proceed and, preferably, at least 3 moles of orthoethylate per mole of steroid are used. No more than a 5: 1 ratio is used, because a higher ratio does not lead to any particular advantage in terms of reaction speed and other conditions.

. In order for the method according to the invention to proceed satisfactorily it is important that the solvent system used is a system in which an appreciable amount of the solvent consists of ethanol, i.e. that at least and preferably about 50% by weight of the solvent system consists of ethanol. One can use up to 100% ethanol, although it is preferable to use an auxiliary solvent as discussed below. The system must also be free-skin anhydrous. Other compatible solvents that can be used in the system are those that are freely miscible with ethanol in all proportions. These solvents include oxidized hydrocarbons, such as e.g. aliphatic ethers and cyclic ethers, such as glycol ethers, dioxane, tetrahydrofuran and tetrahydropyran. Particularly useful in this regard are the dimethylated polyethylene glycols represented by the formula: OH 2 O (CH 2 CHO), which is an integer is from 1 — U. These compounds are generally referred to as "glyms", i.e. glyme (n = 1), diglyme (n = 2} s triglyme (n = 3) and tetraglyne (n = * 0). Each of these compounds can be used alone or in combination as a compatible co-solvent with ethanol. the waste according to the invention A particularly useful mixture consists of 50% by weight ethanol and 50% by weight / glyme.

Furthermore, it is necessary to include a catalytic amount of a strong organic acid or sulfuric acid as a catalyst for the method of the invention. Suitable organic .30 acidic catalysts are e.g. n-toluenesulfonic acid (? T3A), 2,1-dinitrozenesulphoric acid, and trifluorazic acid.

Preferably, voorkeur3Λ or trifluoroacetic acid is used. A catalytic amount of the catalyst is the amount necessary for the reaction to proceed at a reasonable rate. Generally, this amount will be from 0.1 to 20% w / w based on the total weight of the steroid, and is preferably about 8%. "7 _" spring 1-spring.

The reaction irregularities under which the method according to the invention is carried out are not particularly critical, but si.ir. generally known in the art. Ribbon the temperature in the range from 0 - 00 ° C, preferably in the range from 20 - 20 ° C, because a higher temperature often reduces the total yield due to degradation losses. pressure on the reaction mixture may be atmospheric, reduced or elevated near the atmosphere, it is generally carried out under atmospheric conditions, the time required for the CF of the invention to be free to sanen just depends on the reaction temperature because the reaction proceeds slower at lower temperatures, but generally lies between 5 min and 3 hours, although at 20 ° C ° C no more than half an hour for the entire reaction needed to expire.

The reaction vessel which can be used in the working invention of the present invention can be either a vessel for a discontinuous process or a vessel for a continuous process. Preferably, the vessel is a convenient vessel for a discontinuous process, into which the various materials required to carry out the process according to the invention are introduced, and the materials being reacted just so that the materials are reacted. reaction can take place.

The steroids including the store according to the

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The invention can be used in the 1 T-hydroxy-Δ -pregnin-3-ones, which can dehydrate. between the 11- and 9-carbon atoms of the steroid structure, and therefore the steroids usable in the course of the invention are subject to the compounds of formula VI, wherein R is hydrogen, a hydroxy group, a basket chain alkyl ether with 1-6 carbon atoms or a short chain alkyl ester having just 1-6 carbon atoms, hydrogen or a group OH or OC (0) R ^, Rg is hydrogen or an S- or -3D α-methyl green, a short chain alkyl group with 1-6 carbon atoms and straight or branched chain, R 2 and tezanes can form a group of formula 7, and R 2 is independently hydrogen or a hydrocarbon growth with 1-¾ carbon atoms, X is hydrogen, fluorine, chlorine or broon.

The method according to the invention is usable in the biosphere for the formation of 3-enol ethers which are bag products for the formation of achieve steroids compounds which are anti-inflammatory.

H '' ^ 4 ** Γγ 8300369 «> *. * _ 8 'toire, anti-androgenic, estrogenic, or other activity display., Such as.

The components described in U.S. Pat. No. 3,232,915.

Thus, among the compounds for which the process of the present invention is particularly suitable for forming the corresponding 3-enol ethyl ether include the following: 113.17a-dihydroxy progesterone; 110,17a-dihydroxy-160-ethyl progesterone; 110,17a-dihydroxy-16a-diethyl progesterone; 110.17a-1-hydroxy-16a-1-ethyl-progesterone-17-acetate; 10 corticosterone (110,21-dihydroxy-3,2O-dioxopregn-H-ene; corticost ero n-21-acetate cortisol (113,17a, 21-trihydroxy-3,20-dioxopregn-k-ene); 16a-hydroxy -cortisol-16,17-acetonide 16a-hydroxy-cortisol-16,17-acetonide-21-acetate 15 cortisol-17, 21-diacetate 160-methyl-cortisol; 16a-raethyl-cortisol; 16a-methyl-cortisol- 21-acetate; cortisol-21-ethyl ether; 20-l6a-methyl-cortisol-21-hexyl ether; l6a-methyl-cortisol-21-acetate; l6a-nethyi-cortisol-21-pivalate; cortisol-21-acetate; cortisol-21 propionate, cortisol-21-butrate, and the corresponding 6-halogen derivatives of the above-mentioned compounds, such as the 6-bromine, 6-fluorine or 6-chloro derivatives, preferably the chlorine and fluorine derivatives, such as eg 6a-chloro-cortisol δα-fluoro-cortisol 30 6a-luor-16a-hydroxy-corti sol-1 6,17-acetcni de

Sa-chlocr-16n-hydroxy-corti sol-1C, 17-acetonide 6a-fluoro-16a-netby1-cortisol 6a-ch.lcor-16a-r.ethyl-cor ti sol 6i-fluoro-16a-r. ethyl l-cortisol-21-acetate 35 6a-ckiopr-1 <D ar.et ''. yi-ear isol-21-acetate

It should be noted that the sales volume (Du * Si ^ ♦ 8300369 3% J.

* according to the invention can be used for preparing a 3-enol ether with e.g. a 3-oxopregn-4-one which is unsubstituted in the 6a position or is halogen substituted in the 66 position. When the method is used in the latter case, the 5 δβ-halo steroid is brought into the solvent at room temperature in the presence of the acid catalyst, but in the absence of triethyl orthoacetate for a time sufficient to react the 6a-halo steroid. (generally 10 minutes to 1 hour, preferably 20-40 minutes at room temperature). Then, the triethyl orthoacetate is reacted with the 6a-halo steroid in the solvent to form the 3-enol ether.

When the starting sterol structure contains a hydroxy group in both the 21 and 17 positions, a 3-enol ether structure according to formula 8 results, in which X and the above 15 have the meaning. The presence of such a structure is not harmful since the 17,21 orthoester is partially hydrolyzed during subsequent steps, such as chlorination or bromination, and can be completely recycled back to the 17,21-dihydroxy compound by transesterification or under basic am -20 positions.

However, such a reaction does not use additional triethyl orthoacetate, and for economic reasons it is preferred that an alkyl ester, e.g. acetate, in 21st place.

Another aspect of the invention is a process for the preparation of 6-halo-Alpregnene-3-one intermediates by first forming the enol ether as discussed above and then halogenating in the 6-position.

Halogenation, i.e. bromination, preferably chlorination, can be carried out by halogenation in the 6-position by any known method. Halogenating agents are e.g. N-chlorosuccinimide, N-bromosuccinimide and N, Nr-dichlorohydantoin.

In carrying out the halogenation step, the 3-enol ether is first separated from the reactants and the solvents in the first step, then the halogenating agent is reacted with 3-enol ether in a suitable inert solvent under conditions sufficient to cause the formation of the 6-halogen & 4-compound. A suitable solvent is a solvent which does not react with the 3-enol ether or the halogen 8300369 10 ra ring additive which is detrimental to the reaction. Usable. solvents are, for example, oxidized hydrocarbons, such as tetrahydrofuran, dioxane and diethyl ether, acetone, acetic acid or mixtures thereof. Preferably, the reaction is carried out under neutral conditions, i.e. at pH 57 and at a temperature in the range from -5 ° C to + 25 ° C, preferably around 0 ° C. .... *.

More specifically, the halogenation is carried out by reacting the enol ether with dimethyl-N 2 -N-dichloro-hydantoin in a buffered acetone solution at a temperature of 10-5 ° C to + 5 ° C for 60 min.

According to yet another aspect of the invention a. 1 * 6 provides this method for the total synthesis of o-halogen-Δ '-pregnadiene-113,17a, 21-triol-3,20-dione and 6-halogen-A * J ^ -pregnatriene- 113, 17a, 21-triol-3,20-diones, especially the 6-chloro compounds, disclosed in US Patent 3,232,9 5. Both the dienes and the tries possess anti-inflammatory tarnishing with a minimum of salt retention. The additive is also fragile for preparing compounds from the t6a, 17a acetonide series, and others using the above starting compounds.

In a broad sense, the total synthesis according to the invention can be described on the basis of the accompanying reaction scheme E and the summary below.

(1) The first step is based on the esterification of the starting steroid of formula 9 (of which the meaning above is meaningful) at the 21-hydroxy position to form the corresponding 21-alkyl ester (formula 10). ". (2) The 21-alkyl ester (formula 10) is then reacted according to the main variant of the process of the invention with triethyl orthoacetate in ethanol and preferably glyme with an acid catalyst to form a 3-enol ether as given by formula 11.

(3) The 3-enol ether (formula 11) is in turn halogenated, e.g. chlorinated or brominated, forming e.g. a 63-chloro-A-pregnene-3-one of formula 12.

35 (U) The structure of formula 12 is then reacted with triethyl orthoacetate in the presence of an acidic catalyst in ethanol and preferably glyme to form a compound of formula 13 »an enol ether, (5a). The 3-enol ether (formula 13) can then be treated for 1 U 6 with the direct formation of Δ '1 -pregnatriene (formula 5) or (5b) The 3-enol ether of formula 13 in k 6, first react to form a Δ '-pregnadiene of formula 1¾.

U g (5c) The Δ * -pregnadiene of formula tU is in turn dehydrogenated by a method known per se and sheeted in the 1-position to form the corresponding Δ * * -pregnatriene of formula 15.

(6a) The Δ ^ '^ - pregnadiene can then be treated to remove the 21-alkyl ester and form the corresponding 21-hydroxy compound (formula 16), wherein Z is a double bond, or (6b) the compound of formula 1¼ is treated to form a compound of formula 16, where Z is a single bond, which in turn can be converted to the Δ1 '^' ^ - pregnatriene.

A discussion of each of these steps of the total synthesis follows below: (1) In the first step, a compound represented by formula 11, preferably cortisol, is esterified to form a 21-short chain alkyl ester with 2- h carbon atoms in the ester group. This can be done by any method suitable for esterification at the 21-position which is suitable from the literature. In general, this is done by a reaction from. a short chain alkyl anhydride in a suitable solvent, e.g. the reaction of cortisol with acetic anhydride in pyridine at a temperature below 30 ° C. The reaction is clean and complete to form a compound which is given by formula 10, which is preferably cortisol 21 acetate. Propionic anhydride or butyric anhydride can be used in place of acetic anhydride.

(2) In the second step, the resulting 21-ester from step (1) is first isolated and then reacted with triethyl orthoacetate according to the main feature of the inventive method as discussed above to the corresponding s% 8300369 12 * 3 -enol ethyl ether as given by formula 11. Bi, i preferred -. formula 11 is the 3-enol ether of cortisol-21-acetate.

Although it is preferred to first use a compound of formula 9, e.g. Cortisol, to react with acetic anhydride or to form the corresponding 21-acetate, the compound of formula 9 may also be reacted from the beginning with triethyl orthoacetate without having to go through the intermediate preparation of the 21-acetate. By reacting a compound of Formula 9 to form triethyl orthoacetate, a small amount, i.e. 10-15% of 10 is an intermediate, 17.21-orthoester, formed with the enol ether carbon formula 11, wherein R is hydrogen. The presence of the 17,21 orthoester is not detrimental to the overall reaction because it is hydrolyzed in the subsequent chlorination step under the acidic conditions. However, because the formation of the 17,21 orthoester is accompanied by reaction with additional triethyl orthoacetate and because the reaction of a compound such as cortisone with acetic anhydride in pyridine is so clean and the formation of the corresponding 3-enol ethyl ether is complete and rapid in step 2, it is preferable to first form the 21-ester before reacting it with the triethyl orthoacetate. This preferred route 20 is therefore shown in the reaction scheme.

(3) After isolating the 3-enol ether (Formula 11), it is halogenated to form a 6-halogen compound as given in Formula 12. The halogenation step is either a chlorination or a bromination step as discussed above.

(H) The compound given by formula 12 is a ββ-halogen-substituted compound. Before it can be reacted with triethyl orthoacetate to effectively form a 3-enol ether as given by formula 13, it must be halogen. converted into a 6ct halogen. This is done by placing the ββ-substituted compound (formula 12) in an inert solvent at room temperature (20-25 ° C), since a small amount of an acidic catalyst is added and the temperature is added for 1 hour less, preferably 30 minutes or less. Preferably, this is carried out in a solvent such as glyme in the presence of 1% by weight or less of a strong organic acid catalyst such as trifluoroacetic acid or p-toluenesulfonic acid. The conversion to the 6a halogen compound is completed in less than 1 hour.

^ 8 Γθ 0 3 6 9 * (.. T3 ....

generally in less than half an hour. Ethanol and triethyl orthoacetate are then added to the reaction mixture and the reaction mixture is reacted according to the hSt principal feature of the invention to form the 3-enol ether represented by formula 13.

After isolation, the intermediate of formula 13 can then be converted into the desired final product by various methods.

(5a) The compound represented by 1 U 6 formula 13 can be reacted directly to form the Δ ′ 1 -tO pregnatriene of formula 15. In a one-step method, the compound of formula 13 e.g. react with 2,3-dichloro-k, 5-dicyanobenzoquinone (DDQ) and an essentially anhydrous suitable oxygen-containing carbon 1 k 6 hydrogen solvent, such as dioxane, at room temperature on the Δ * * -pregnatriene-21-ester with formula 15, which in turn can be hydrolyzed under basic conditions or transesterified to form the 21-hydroxysteroid of formula 16, wherein Z is a double bond.

(5b) Because of higher yields, a two-stage method is preferably used, in which a structure of formula 20 1¾ is first formed, and in turn it is dehydrogenated at the 1-position to form a compound of formula 15. Either the compound of formula Either that of formula 15 can then be hydrolyzed to form a compound of formula 16, wherein Z is either a single or double bond.

The compound represented by Formula 1k is first formed by reacting a compound of Formula 13 with a suitable oxidizing agent (a tetra-substituted 1, U-benzoquinone) at low temperature (ie 0-10 ° C) in a moist oxygen-containing solvent, such as dioxane or acetone with 25% by weight or less of water.

A particularly suitable oxidizing agent is 2,3-dichloro-5,6-dicvane benzoquinone (DDQ). Generally, this reaction is completed in 2 hours or less.

(5c) The k, 6-pregnadione as represented by formula I is isolated and then dehydrogenated in the 1-position to form the compound of formula 15. Dehydrogenation can be performed by chemical or microbiological means known to those skilled in the art. The k, 6-pregnadiene of formula 1k is first isolated 4 8300369 ... Ilv before it is dehydrogenated according to the subsequent step. In the selective chemical dehydrogenation in the 1-position, a compound of formula I4 is reacted with a suitable oxidizing agent under fiber free conditions in a suitable solvent, such as an oxygen-containing hydrocarbon, e.g. in alcohol, dioxane or acetone, at a temperature above room temperature to reflux temperature. A suitable oxidizing agent is DDQ, and the suitable solvents include xylene, toluene, amyl alcohol, dioxane and acetone. Preferably, the material is refluxed in the solvent for a period of time sufficient for the dehydrogenation to take place. This is generally 1-20 hours with chloroanil in amyl alcohol or 12-16 hours in xylene. With DDQ in vessel-free acetone, only b hours are needed at reflux temperature. . "

Preferably, however, the chemical methods of dehydrogenation at the Δ-position are carried out by the method of bromination in the 2-position and dehydrobromers between 1 and 2 to form the double bond. Bromination is carried out by reacting a suitable k 6 brominating agent with the Δ * -pregnadiene in a suitable solvent for a period of time sufficient to complete the reaction. Suitable brominating agents are e.g. bromine in combination with bromine hydrogen and this can be used in acetic acid at room temperature for a reaction time of 10 minutes, whereby a reaction product is obtained in a yield of 85% or more.

A particularly useful brominating agent for the 2-bromination is pyridinium hydrobromide perbromide or trirethylphenyl ammonium tribromide in tetrahydrofuran, however this is carried out at a temperature of 30 ° C or less, preferably at 20-25 ° C.

The resulting 2-brominated product is then dehydrobrominated by reacting the 2-bromine product with a dehydrobrominating agent. Characteristic dehydrobromination reactions can be found on biz. 213-218 to Steroid Reactions, An Outline For Organic Chemists by Carl Djerassi, Holden-Day, 1963. A particularly preferred method relies on refluxing the 2-bromo-A * -pregnadiene with lithium carbonate and lithium bromide in DMF for 5 hours .35 or less, preferably less than 3 hours, at a temperature of 100-110 ° C.

(5d) Alternatively, the compound 8300369 of formula 14 can be dehydrogenated using microbialogic agents, ie the compound is bathed by a fermentation process using either (i) growing microorganisms such as arthobacter simplex, or (ii) cell-free enzyme preparations or short chain alkanol or alkanone dried cells in the presence of a hydrogen acceptor. However, since microorganisms and enzyme preparations also have some esterase activity, it is preferable to first form the 21-hydroxy compound by hydrolysis or transesterification, and then treat the compound to form the Δ * * compound. .

An example of the method using a growing microorganism is the method described in US Pat. No. 2,837,464, in which a Δ-3-keto-pregnene is subjected to the action of a culture of a member or a group consisting of nit corynebacterien simplex (also referred to as arthobacter simplex) and corynebacterien hoatii. In general, the introduction of a double bond proceeds satisfactorily at pH 7.6-8 at a temperature of 32-37 ° C.

An example of the callous-free enzyme preparations in the presence of a hydrogen acceptor is the method described in U.S. Patent 3,047,469. In this method, the steroid, which is unsaturated at the 1,2-position, is allowed to act in a mixture of a ring A dehydrogenase extract from a microorganism such as corynebacteria, the extract being essentially free of living cells.

Other microorganisms that can be extracted include nocardia, corynebacterium, mycobacterium, cylindroparpon and bacterium. The hydrogen carriers which can be used in conjunction with the cell-free extract according to the invention are oxidation-reducing reagents, for example, dyes such as potassium ferrocyide; thiazines and imine derivatives, such as e.g. methylene blue, and phenacine methosulfate; benzoquinones and imine derivatives, e.g. ortho-quinone, toluylene blue chloride; naphthoquinones, such as cresyl blue, and indophenols, especially 2,6-dichloroindophenol.

In the cell-free extract process, the extract can be directly mixed with the steroid starting material and the hydrogen carrier added to the mixture or it can first be mixed with the hydrogen carrier and then in contact with 8300369 ...... 16 '' the steroid is brought. A concentration of the hydrogen carrier is not critical and any concentration starting with a catalytic amount up to a stoichiometric amount equal to the concentration of the steroid can be used. The pH and temperature that occur during dehydrogenation are not critical. The temperature can be in the range of 20 -5 ° C, and is preferably at 25-35 ° C. The pH can be acidic, alkaline or neutral and is preferably in the range of 6.0-8.0.

If desired, to maintain the pH at a certain value, a buffer material such as an inorganic phosphate, e.g. sodium phosphate, into the reaction mixture. The reaction mixture is allowed to stand for an appropriate time until the ring A dehydrogenation is complete, which usually takes 1-20 hours. *

A particularly effective dehydrogenation process is discussed in U.S. patent application serial number 550.2¼, U 6 15 filed on the priority date of this application, wherein a Δ * compound, such as a compound of formula 16, wherein Z is a single bond, is dehydrogenated selectively with the aid of arthobacter simplex (also referred to as corynebacterium simplex) in the presence of a hydrogen acceptor, such as a quinone or quinone derivative. The process described in the above-mentioned patent application is particularly suitable for the preparation of 6-chloro-α-β-β-pregnatriene-1,15,17 <x, 21-triol-3,20-dione from h 6 the corresponding Δ * -pregnadiene. A preferred strain of arthobacter simplex, iJRRL No. V-8055 is publicly available and can be obtained from the Northern Regional Research Laboratory in Peoria, 25 Illinois.

Hydrogen acceptors useful in the process of the invention are selected from quinone compounds and derivatives thereof and include benzoquinones such as tetramethyl-. p-benzoquinone and 2-isopropyl-5-methyl-p-benzoquinone; naphthoquinones, such as menadione and 2-hydroxy-1Λ-naphthoquinone; indophenols, such as 2,6-dichloro-indophenol; and menadione sodium bisulfite. It is advantageous to keep the pH in the range of 7.5-8.5 during the Δ1 dehydrogenation while keeping the temperature at 23-33 ° C, preferably around 28 ° C. Once a suitable culture medium is obtained, the amount of substrate added to the medium can even be 0.7 g / l medium, but the preferred substrate concentration is 0.5 g / l medium. The quantity- 8300369. IT ..

* '' Hydrogen acceptor can vary within a wide range, i.e. the molar ratio of substrate to hydrogen acceptor can range from 30: 1 to 10: 1. When menadione sodium bisulfite is used as the hydrogen acceptor, the preferred substrate to acceptor ratio is 15: 1.

The steroid can be added to the medium as a suspension in a suitable solvent, such as water, as a solution in a solvent, such as ethanol, acetone or dimethylfoririamide, or in finely divided forms, such as solid micronized particles. The hydrogen acceptor is added to the medium as a solution in the solvent, such as ethanol or dimethylformamide, or in the case of menadione sodium bisulfite as an aqueous solution.

After addition of substrate and hydrogen acceptor, stirring and aeration of the medium is continued for 3-T hours until dehydrogenation is complete. During the course of the fermentation reaction, the course of dehydrogenation can be monitored with silica gel, thin layer chromatography of solvent extracted samples.

When dehydrogenation is complete, the product, δ-chloro-A ^ * ^ * ^ - pregnatriene-11 £ 3.17a, 21-triol-3.20-dione is recovered from the fermentation medium by extraction with a suitable solvent, such as chloroform, methylene chloride or methyl isobutyl ketone.

The solvent of the solution is evaporated to obtain a senikpistalline product which is purified by silica gel chromatography. The product can be further purified by recrystallization from a suitable solvent, such as e.g. isopropyl acetate, ethyl acetate or a mixture of acetone and water.

The examples below serve to illustrate the invention.

Example I

20 g of cortisol 21 acetate were added to 100 ml of absolute ethanol and 100 ml of ethylene glycol dimethyl ether (glyme).

The solution was heated to 0 ° C and 2 g of p-toluenesulfonic acid (? 7 SA) followed by 2 h g of triethyl orthoacetate were added. The reaction was stirred at 35 ° C 10 ° C until the solution was complete. The reaction mixture is stirred at 0 ° C for an additional 0 min, cooled to room temperature and 2 ml of pyridine 830036918dine are added. The reaction mixture is poured slowly into a mixture of 520 ml water and 52 ml hexane. After 30 min at 0-5 ° C, the product was filtered and washed with water and then with 50 ml of hexane and the product was dried in vacuo at 40 ° C. The yield was 90-104 wt.%. This is an example of the method according to the invention, from which it appears that the yields are essentially quantitative for this particular process.

Example II

*

This example is performed to show the difference in yield and product between the method of the invention and a method of the prior art. In this particular example, 10 g of cortisol-21 acetate are added to 100 ml of absolute ethanol, 10 ml of triethyl orthoformate and 0.300 g of 2,4-dinitrobenzene sulfonic acid. The mixture is stirred at room temperature until the solution is complete. The reaction mixture is stirred for an additional 15 min and 1 ml of pyridine is added. The solution is concentrated to half the volume and 10 ml of water are added. The concentration is continued until crystallization occurs. About 100 ml of water are added and the product is filtered off, washed well with water and dried to give the corresponding 3-enol ether. In this particular case, some dehydration product was found which was completely missing in Example I, and about 10% of unreacted material remained in this process, as well as a small amount of other undesirable products, while in comparison to Example I, virtually no unreacted material was left as determined by thin layer chromatography (TLC).

Example III

This example demonstrates the need for the presence of triethyl orthoacetate in the process of the invention. In this example, the technique and amounts of Example I were used, except that triethyl orthoformate was replaced with triethyl orthoacetate. Analysis of the final products by thin layer chromatography (TLC) indicated that a small amount of starting material was still present, but that there was a significant amount of intermediate products and about 10-15% of the Δ11 ^ the HVR product.

8300369 19_

Example IV

In this example, 20 µl of cortisol was added to 100 ml of absolute ethanol and 100 ml of ethylene glycol diethyl ether, as in Example 1. The rest of the method as described in Example I was followed in this example except that 0.3 g of 2,1-dinitrobenzenesulfonic acid and 10 g of triethyl orthoacetate were used. The results showed an almost complete reaction producing about 15% of a 17.21 orthoester from the 3-enol ether. The presence of this product is not harmful in the process of the invention, since the product can be further reacted and, at the end of the series of reactions, the 17, 21 orthoester can be easily hydrolyzed, if desired, to form the corresponding 11β , 17a, 21-trihydroxy steroid.

Example V

T5 The same procedure as in Example III was followed except that no ethylene glycol dimethyl ether was used. At the end of the reaction series, there was still a significant amount, i.e., about 10% of the original starting material, which had not reacted. This once again indicates the need to have triethyl ortho-20 acetate present in order to complete the process of the invention.

Example VI

This example shows that the process of U.S. Pat. No. 3,087,927 gives the desired product.

In order to further emphasize the importance of the presence of the triethyl orthoacetate and also the importance that a predominant part of the solvent consists of ethanol, in this example 30 g of cortisol-21-acetate are suspended in a solution prepared from 300 ml dioxane, 30.0 ml of trimethyl orthofornate and 1.20 ml of absolute methanol. To the rapidly stirred suspension * 0.60 ml of concentrated sulfuric acid are added dropwise. The suspension thins progressively during the first few minutes and complete dissolution is effected within 6 min. 1.80 ml of pyridine are added, after which a faint purple discolouration immediately disappears and the resulting solution is pale yellow in color. The entire operation up to this point is performed at room temperature. The diluted reaction solution is placed in an 8300369. 20 ♦ * Separating funnel, the stem of which protrudes below the surface of 300 ml of a water-ice mixture contained in a large beaker.

The reaction mixture is slowly added to the vigorously stirred ice-water mixture over 2-3 hours.

The solid that forms is left in the solution overnight at 5 ° C and then removed by filtration. The product is washed well with water and air dried to give 28.7 g of product. TLC analysis of the product shows that the entire product is comprised of 21-acetate.

Example VII

In this example, the same method as in Example VI was followed, except that the absolute ethanol was used instead of the methanol and triethyl orthoacetate was used instead of the trimethyl orthoformate. Following the method of Example VI, it was found that virtually no reaction occurred. This shows the importance of using a predominant amount of ethanol and that the disclosure of U.S. Patent 3,086,927 is ineffective.

From the above examples as summarized in Table A, it can be seen that the process of the invention in which the steroid is reacted with the triethyl orthoacetate in a solvent consisting of a major amount of ethanol and an oride-appropriate amount of an oxygen-containing hydrocarbon solvent, like glyme, gives results that are better than the prior art.

8300369 '

* I

21

* Table A

i £ ar 4 », TEOA TEOF EtOH GLYME H CAT Results I (invention) X X X X Rxn complete II (state of the art) - X X X Rxn incomplete 5 III (state of the art) - X X X X Rxn incomplete; 11 (9),., ...

Δ dehydration product f IV (invention) X XXX Rxn complete; vessel 1T, 21 orthoester 10: (not harmful) V (state of the art) - X X X Rxn incomplete VI (state of the art - - TMOF under- Dioxan X, only

U.S. Patent 11 (9). . , ..

script 3.087.927) arranges ^ 15 MeOH product VII (state of the art - X under dioxan X no Rxn

U.S. Patent No. 3 O87.92T) arranges X TMOF = trimethyl orthoformate; less than methanol (MeOH); 20. dioxane used as main solvent 35¾ TEOA = triethyl orthoacetate TEOF - triethyl orthoformate EtOH - ethanol • φ »^ ^ § H cat - acid catalyst - differs, see leather above 25 Rxn - reaction" X "- present material" - "- absent material Φ Cortisol used as a starting material.

Preface VIII

The series of reactions below gives a particularly effective method for the re-derivation of 6-chloro-A-1-impregnatriene-118,17, 21-triol-3,20-dione from cortisol.

The reaction conditions are representative of the conditions suitable for use in as much as 35 'of the limited and ample sin of the invention invention and are therefore preferred. However, the representative reaction conditions mentioned hereinabove, while preferred, should not be interpreted in a limiting sense.

8300359 22 .....

* Formation of Cortisol 21 Acetate. Response according to schedule F.

Preparation Wi i7.e:

A 1 L flask is charged with 1 * 00 ml 5 pyridine and 100 g {0.276 mol) hydrocortisone (cortisol) are added until the cortisol partially dissolves. While the temperature is kept below 30 ° C for 10 minutes.

163.3 g (1.59 mol) of acetic anhydride. The mixture is allowed to stand at room temperature for 1 hour until the reaction is complete. 300 ml of water are slowly added to the reaction mixture while keeping the temperature below 1 * 0 ° C. The reaction mixture is left to stand for 20 minutes and then transferred to a three liter flask. After 20 minutes, 1500 ml of saturated aqueous sodium chloride solution are added. The mixture is cooled to 10 ° C for 1 hour and then filtered. The product is washed with water and dried in a vacuum oven at 50-60 ° C. Yield 110.1 * g (110.1 * w / w 99.2% of theory).

Reaction with triethyl orthoacetate to form the 3-enol ether and subsequent 6B chlorination. 20 Reactions according to scheme G.

Method of preparation;

A 2 L flask is charged with 550 ml ethanol, 330 ml 1,2-dimethoxyethane (glyme) and 110.1 g (0.272 mol) cortisol 21 acetate. The mixture is heated to 1 * 0-1 * 2 ° C and a solution of 9 g of p-toluenesulfonic acid in 200 ml of 1,2-dimethoxyethane followed by 116 g of triethyl orthoacetate is added. The temperature is kept at 38-1 * 2 ° C. After 20 min, 2.5 g of p-toluenesulfonic acid are added. The mixture is kept at 38-1 * 2 ° C for 30 min, then cooled to 8-10 ° C and 12 ml of pyridine are added, followed by a solution of 2.7 g of sodium acetate in 50 ml of water. The pale yellow solution is added to a mixture of 1U g of sodium acetate in 2l * 50ml water and 288ml hexane and then cooled to 10 ° C, stored for 20min, filtered and washed with 800ml water containing 1g sodium acetate, followed through 220 ml of hexane.

The wet cake (about 200 g) is placed in a cold (10 ° C) mixture of 13.7 g of sodium acetate in 18U ml of water 8300369 ... 23 and UUo ml of acetone and cooled to 0-5 ° C. A solution of 27 g of "Halane" (registered trademark for 1,3-dichloro-5,5-dimethyl-hantoantoin) in 720 ml of acetone is added while keeping the temperature below 5 ° C. The mixture is kept at 0-5 ° C for min. Then a solution of 9.2 g of sodium bisulfite in 132 ml of water is added and the mixture is slowly taken up in 2200 ml of water over a period of 30 min and cooled. to 0-5 ° C, stored for 1 hour, filtered and dried in a vacuum oven at ^ 5 ~ 50 ° 0. Yield: 107.2 g (97.1 w / w & 9.5% of theory). * 70 Reaction with trichlorothoacetate to form a 3-enol ether and subsequent A * worm;

Response according to scheme H.

Preparation:

A 2 1 flask is charged with 10 µg (0.237 75 mol) 6g-chloro-11S, 17a, 21-trihydroxypregn-U-3,20-dione-21-acetate (from the previous step), 500 ml 1, 2-dimethoxyethane and 3.03 g of p-toluenesulfonic acid and stored at 20-25 ° C for 30 min. 500 ml of ethanol are added, followed by 91 µg (0.563 mol) of triethyl orthoacetate. The reaction mixture turns dark red and is stored at 20-25 ° C for min. And then cooled to 15 ° C and a solution of 13 g of sodium acetate in 6 ml of water is added. The temperature is kept below 20 ° C and 220 ml of methylene chloride are added, followed by 1000 ml of water, which are slowly added while the temperature is kept below 25 ° C. The mixture is stirred for 15 minutes and the bottom organic layer is separated. The upper aqueous layer is extracted with 3.75 ml of methylene chloride. The organic fractions are combined and washed with a solution of 1.3 g of sodium acetate in 260 ml of water.

The methylene chloride extract (about 900 ml in total) is separated and concentrated in vacuo to about ml and during the distillation a mixture of 850 ml of dioxane and 1.3 ml of pyridine is added while the volume is at about ^ 0-b5G ml is kept. The mixture is distilled to a final volume of 100 ml (no methylene chloride should be present at this time) and 300 ml of dioxane are added. The mixture is cooled to 10 ° C and 65 ml of water are added, after which it is cooled to 0-5 ° C. A solution of 75 g DDQ in 300 ml dioxane is added over a period of 1 hour while keeping m 8300359 2h, the temperature at Q-5 ° C. The addition funnel is streaked with 30 ml dioxane and the mixture left for 30 min. Stored at 0-5 ° C. A solution of 30 µg of sodium bisulfite in 87 ml of water is added, and the temperature is kept below 10 ° C. The slurry is concentrated under vacuum to 600 ml. The slurry is slowly added to 1000 ml of water under vigorous stirring, then cooled to 10 ° C and left for 3 hours. The product mixture is filtered and fused just a little more. The moist solid is added to 1500 ml of methylene chloride, stirred for 1 hour, filtered and washed with 100 ml of methylene chloride. The solid is added to 1 + 00 ml of methylene chloride, stirred for 20 min, filtered and washed with 100 ml of methylene chloride. The methylene chloride solutions are combined and stirred with 1000 ml more. The organic layer is separated and the blurred layer is extracted with 50 ml of methylene chloride. The methylene chloride extracts are concentrated from 15 to 1 + 00 ml and 1000 ml of acetone are added with distillation while the volume is kept at about 360-1 + 00 ml. The slurry is distilled to a final volume of 300 ml and cooled to 0-5 ° C, incubated for 30 min, filtered and washed with 82 ml of cold (0-5 ° C) acetone. The product is dried in vacuo at 50 ° C. Yield: 80.3 g (77.2 / 20,; 77.5 # of theory). .

A ^ Formation and subsequent hydrolysis

Reactions according to scheme J,

Preparation: 50 g of RS-1 + 232 acetate (from the previous "25 stage, containing about 10% acetone) are added to 350 ml of methylene chloride. 30 g of neutral alumina are added and the mixture is stirred for 1 hour. The alumina is filtered and the solution is concentrated to a volume of 50 ml. Tetrahydrofuran (1 + 00 ml) is added and the distillation is continued until a boiling point of about 65 ° C is reached. The mixture is cooled to 25 ° C and a solution of 3 * + g of pyridinium hydrobororide perbromide in 130 ml of tetrahydrofuran is added The reaction is stirred at 25 ° C for 20 min and 3 ml of acetone are added The reaction mixture is filtered and the filtrate concentrated to a volume of 50 ml.

35 Dimethylformamide (1 + 00 ml) is added, followed by 22.5 g of lithium carbonate and 8.1 g of lithium bromide. The system is flushed with stitching 8300368 .... 25. .

·; The substance and the reaction mixture are heated at 105 ° C for 2 hours, concentrated in vacuo to 200 ml, cooled to 6 ° C and 50 ml of acetic acid are added, followed by TO ml of water. The reaction mixture is slowly poured into 1600 ml of water. After 1 hour at 25 ° C, the product is filtered off and washed with water. The product was dried in vacuo and dried at 60 ° C.

Yield U1.5 g (83 w / w). The product is recrystallized twice from acetone. Purification yields: 78.8 w / w.

6-Chloro-11β, 17cc, 21-trihydroxypregna-1, k, 6-triene-3,20-dione is formed by transesterification in vessel-free methanol in the presence of a small amount of potassium carbonate.

Example IX

The procedure of Example VIII is followed for the preparation of 6-chloro-11 {5, 17a> 21-trihydroxypregna-h, 6-diene-3,20-dione-21-acetate, which is converted to the corresponding 21-hydroxy -15 'compound by reaction with vessel-free methanol in the presence of a small amount of potassium carbonate,

Example X

This example provides a method for h "* formation using microbiological means (i.e., growing cells with a hydrogen acceptor), a. Fermentation.

A culture of Arthobacter simplex NRRLB-8055 is incubated for 6 days at 28 ° C on an agar disk of the following composition: Culture medium agar (Difco). 20 g

Glucose v 10 g

Yeast Extract (Difco) 10 g

Distilled water 1 1

A loop full of the surface growth of the disc is used to inoculate two 300 ml nephrococcal flasks each, each containing 50 ml of the following sterile nutrient medium (b): 1 Hais steep liquid 5 g

Yeast extract (Difco) 1 g 35 Cerelose (pract. Glucose monohydrate) 0.5 g

Distilled water 1 * 1

pH = T

8300369 26

The flasks are incubated at 28 ° C on a rotary shaker at 280 rpm using a 2.5 cm stroke. The incubation is completed in 2 hours or when the turbidity of the stock reaches 185-180 Klett units measured on a Klett-Suramerson photoelectric 5 colorimeter equipped with a no.66 filter and set to 0 with sterile medium, then the entire contents of both flasks used to inoculate 900 ml freshly sterilized medium b contained in a 2 L glass fermentation flask. The incubation of the fermentation flask is continued at 28 ° C while the aeration is kept at a volume of one.

10 air / vol. medium / min, and stirring is performed at 300 rpm. 11a 2k hours 500 mg of 6-chloro-113,17a, 21-trihydroxypregna-k, 6-diene-3,20-dione (prepared as in Examples VIII and IX) are added to the fermentation as an ethanolic solution ( 25 mg / 0.1 ml ethanol). At the same time, 00k 26mg mg menadione sodium bisulfite were added to the fermentation t5 as a filtered sterilized aqueous solution (26mg / 10ml). Incubation is continued as above. The reaction is completed in 3-5 hours.

b. Isolate and characteristics

The fermentation broth is extracted 3 times with 500 ml portions of chloroform. The combined chlorophora extracts are dried over anhydrous sodium sulfate and concentrated to dryness under vacuum. The semicrystalline residue obtained is purified by chromatography on silica gel. The product is eluted with mixtures of chloroform and acetone. The fractions containing the yielding product are combined and evaporated to dryness to yield 5 mg (yield 95% of theory) of 6-chloro-d-4-di-sodium-1,17,1a, 21-triol-3 20-dione, which are then recrystallized from isopropyl acetate.

Similarly, using menadione and tetramethyl-β-benzoquinone instead of menadione sodium bisulfite, a corresponding conversion of 6-chloro-A * -pregna-diene-113,17a, 21-triol-3.20 was obtained -dione in 6-chloro-A1 * 5-5 -pregnatriene-113,17a, 21-triol-3,20-dione.

Example XI

An inoculum of Arthobacter simplex is prepared as in Example X.

8300369 v 27 ....

5 ml of the 2-hour seed culture are then used to inoculate four 250 ml Erlenmeyer flasks, each containing 50 ml of medium b (Example I). The flasks are incubated at 28 ° C on a rotary shaker at 280 rpm using a 2.5 inch diameter stroke. After 2 hours, 25 mg of S-chloro-d-4-pregnadiene-IIBiVcti-1-triol-3,20-dione (prepared as in Example VIII and Example IX) are dissolved in 0.1 ml of ethanol, to each of the flasks added. At the same time, 0.78 mg of 2-isopropyl-5-methyl-p-benzoquinone in 0.2 ml of ethanol is added to one of the flasks. To a second flask are added 0.83 mg of 2-hydroxy-1,1'-10 naphthoquinone and to a third flask are added 1.2 mg of sodium salt of 2,6-dichloroindophenol dissolved in 0.5 ml of HgO. No water or acceptor is added to the fourth flask, which serves as a bianco. Thin layer chromatography analysis of solvent-extracted samples after a contact time of 7 and 2 hours indicates an increased formation rate and percentage formation of the product 6-chloro-A-1 -pregnatriene-118,17a, 21-triol 3.20-dione compared to an untreated bianco.

Example XII

This method follows the method of Example 1, except that 2 g of trifluoroacetic acid are used in plants of PTSA as an acid catalyst. Corresponding yields are obtained.

Example XIII

In this method, the method of Example I is followed, except that 2 g of sulfuric acid are used instead of PTSA as the acid catalyst. Corresponding yields are obtained. .

8300369

Claims (1)

* c S Process for the preparation of 6-chloro-113.17a.21-trihydroxypregna-1,4,6-triene-3.20-dione of the general formula 17, characterized in that (a) cortisol-21-acetate is reacted Brings with triethyl orthoacetate in the present day a catalytic amount of a strongly acidic catalyst in a solvent at a temperature of 0-100 ° C, consisting essentially of about 10 wt% ethanol and about 60 wt% or less of a compatible oxygenated hydrocarbon liquid to form a reaction product which is a 3-enol ether, (b) then reacts the 3-enol ether from (a) with a chlorinating agent in an inert solvent in a manner known per se of 63-chloro-cortisol-21-acetate, (c) reacts this 63-chloro-cortisol-21-acetate from step (b) with a catalytic amount of a strongly acidic catalyst in an inert solvent in itself Self-known manner to form 6a-chloro-cortisol 21-acetate, (d) then reacting this 6a-chloro-cortisol-21-acetate with triethyl orthoacetate in a solvent, which is a mixture of about 40 wt% or more ethanol and 60 wt% or less of a compatible oxygenated hydrocarbon liquid in the presence of a catalytic amount of a strongly acidic catalyst at a temperature of 0-100 ° C to form a reaction product, which is the corresponding 3-enol ether, (e) the 3-enol ether from ( d) oxidizes in a manner known per se to form 6-chloro-133.17a.21-trihydroxypregna-4,6-diene-3.20-dione-21-acetate, (f) the product from (e) in 1 - dehydrogenates in a manner known per se to form 6-chloro-13 3.17a.21-trihydroxypregna-1,4,6-triene-3.20-dione-21-35 acetate or (g) the 3-enol ether from (d) on a per se- 8300369 m *. "29 self-known manner reacts to form 6-chloro-11 (3.17a-21-trihydroxypregna-1, 4,6-triene-3.20-dione-21-acetate, (h) directly to yield the 21-acetate product (e) hydrolyzes or transesterifies to form 6-chloro-lIS.17a.21-trihydroxy-pregna-4,6-diene-3.20-dione. (i) then the product from (h) in a manner known per se in the 1-position dehydrogenates to form 6-chloro-11 (3.17a.21-trihydroxypregna-1, 4,6-triene-3.20-dione or Cj) the product from (f) or (g) hydrolyzes or transesterifies under formation of 6-chloro-116.17a.21-trihydroxypregna-1,4,6-triene-3.20-dione 15 8300368 V t ckoh i 1 C - 0, CK I Η 0H CHV Cl 17 Syntex (U, SA). Inc ., at Palo Alto, California, Ver.St.y.An?eri[ca 8300369 -A - '.ο—,' CH2OH - H-CC0__ «1 = 0 HO 0- ^ H0y-SA | -0H ΗΟγ ^ γΧ-0 0lXX ^ * oW 2. ~ B ~ 2 —-: --- * - TJ 1 -C- '^ o—, ° ^ CH2 O ^^ rL-o / 3: - ^ \ pX. J' 4 CHtOH CH2R HO ~ 00 ^ .r / ° R4 un Y ^^ Vo- ^ p HVNA ^ R '~ * - °>. / ^ V-1. Ri; JJ> Si --ο-cn Rs JUU 5 XX T 6 7 R * ° x -D- _ '' .CH * C-0C2Hs + 2CsHr0H - s-NH ^ Ci + CH4C (OCjHs ^ (1). 11 NH-HCt · CH2 · C (0 O2 · ^. + C2H? 0H - ^ CH3C (0C2H ^ 3 (2) 8 3 0 0 3 6 9 Syntex (USA) Inc., Palo Alto, California, USA. .v.America JNM «« «• ΜΜ» t «WL3 CHgOH CHaOR CR = 0 ru“ 0 un 5 o H · H0v ^ A ~ R «0J ^ CXg * 0S ^ J 10 (2) - J - 'AfiR CH? 0R ni = 0 CH * - = 0. HO ° MD HO ^ TL-R, - $ Pir * »>> iPlr ~ r * 0J ^ AyJ 12 CHjCH.oAA ^ 1 j, a (4) CSR . 'c ^ or HO' C5 <"R ', /, CHjHr chY" ^ "1 —- R - ^ L *. Β0Λΐ1 Jpli_1 *" cai j pR »., (5b) CH.0R a CHfiH * CH3 p (5c) 1 (6a) CH5 - 0 Hoy ^ P \ i. / W ^ \ Ar-R 'r * j ^ w ^ x_t- (rj ^ o ^ M 16 a (6b) ci -F- CHgOH. CNjOAc ch3 | = o ch3 = 0 Η0 \ ^ / \ ψΑ ~ -0Η H0 \ ^ X ^ \ - 0H r-SQ-J A., 0 ^ $ u_) 8300 369 Syntex (USA) Inc., Palo Alto, California, United States America CHjOAc. CHjOAc '—0 = 0 HO HO> ^ \ iAr-OH' fYinH), ·, ΜΓΥ -ifT- ^ CzHjO CHe0Ac ./ = 0 '* HaEane ". Ci' CHjOAc WAC = 0 -0 H ° N / \ / V | 'oh ΗΟ ^^^ ΛγΟΗ | I CK3C (0 Cj'rij) k ^ Γ H * CjHsO J ci. L. a -. •. ". CHjOAc. · . = 0 Η0 ^ \ μΛτ- ° Η DDQ dioxan -X Λ. Λ οί'ν ^ γ 'a. 8300369' f - ** · - '~ J "CH ^ OAc Γ CHi0AC =, 0 · “O 'ΓΐΤ C.HrNHBr, O ^ VY -THF ^ O ^ V Cl. L Cl * J LigCOjy ^ LiBr DMF Cl ^ OH. f CHP Ac = 0 Uo Η0γ ^ ν. / χ ^ -0Η HO ^^^ A ^ '- OH ΐ> Ύ jMeOH. KjC03 o ci a | * \ / ch * r o = o c I. CM / \ C = 0 HO ^^ Va --- 0 CHi -R, όΓ J r ^ -Rz TT Rl 8. 9 x. Syntex (U.S.A.) Inc., at Palo Alto, California, USA St. 830036