CS242122B1 - Brasinolide analogues and method for their preparation - Google Patents

Abstract

The solution relates to brassinolide analogues as new plant growth regulators. These are substances of the general formula I, where R is OX or NHX, while X is H or alkyl with 1 to 6 carbon atoms. For example, R can be OCHp OH, OCH/CH3/CH/CH3/2, NH2, NHC^, NHCH/CH3/2. They are prepared from 2ot, 3c-diacetoxy-7-oxa-6-oxo-23,24-dinor-B- -homo-5ot--cholanic acid via its chloride by treatment with NH3, amines or alcohols and subsequent selective saponification.

Description

The invention relates to brassinolide analogues and a method for their preparation. These substances can be used as plant growth regulators.

Brassinoid, discovered several years ago /R.D. Grove et al.: Nature 281, 216 /1979/, is a very effective plant growth regulator. Substances that differ from brassinolide in the stereochemistry of the side chain /R. J. Thompson et al.: Steroids 39, 89 /1983/ are also highly effective. Experiments show that these compounds increase the formation of leaf area and the yield of bean pods, increase the weight of lettuce heads, shorten the period of its development and support the growth and development of barley plants /U. I. Heudt et al.: Investigation on the mechanism of the brassinosteroid response, III. Technique for potential enhancement of crop production. 10th ann. meeting of the Plant growth society of America, East Lansing, Nich., June 19-23, 1983/. However, these substances are available synthetically only by complex, multi-step processes. Particularly difficult is the synthesis of the side chain /R. Sakakibara and K. Rori: Agric. Biol. Chem. 47, 663 /1983/.

In contrast, the preparation of substances according to the invention allows for simpler technology, while the substances prepared in this way retain high growth efficiency.

The subject matter of the invention is new analogues of brassinolide of general formula I,

-2242 122 /1/,

COR where R is OX or NHX, where X is H or alkyl with 1 to 6 carbon atoms. For example, R can be OCHj, OH, OCH/CHj/CH/CHj/g, NH ₂ , NHC ₂ H ₅ , NHCH/CH _? / ₂ or NHCH ₂ CH/CH ₃ / ₂ . The invention also provides a method for preparing these analogues, the subject of which is that methyl ester of 4-hydroxy-23, 24-dinor-5-cholenic acid /formula III/

converted to the tosylate of formula III,

COOCH ₃ /111/, which is converted in an alkali metal acetate environment or to the ^-hydroxy-3e<.,50<.-cyclosteroid of formula IV, pyridine pre-3-

C00CH ₃

242 122 /IV/, which after oxidation to a ketone is converted in an acidic medium to a hydroxy derivative of formula V

cooch ₂ /V/ and then to the tosylate, from which, upon removal of p-toluenesulfonic acid with lithium bromide in dimethylformamide, a substance of formula VI is obtained,

which, by the action of osmium oxide in the presence of N-methylmorpholine N-oxide, gives a substance of formula VII,

HIM

COOCH.

/VII/

AND

-4242 122 and this is acetylated to diacetate/ which by the action of peracid, preferably trifluoroperacetic or performic/ is converted to a lactone of formula VIII,

which, after saponification and acetylation, gives the corresponding chloride by the action of oxalyl chloride, which, upon reaction with NH^, amines or alcohols with 1-6 carbon atoms and subsequent partial saponification, gives amides or esters of formula 1.

These substances show high efficiency as plant growth regulators, e.g. substances of formula I /R=NHCH/CH^/g, R=NHCH ₂ CH/CHj/g/ have activity comparable to the activity of 24-epibrassinolide in a test based on the stimulation of bending of the 1st internode of bean /WJ Meudt, H. Bennet: Physiol. Plant. 44, 422 /1978/ The following table shows this comparison

T and lump

Effect of brassinolide analogues on the stimulation of bending of the 1st internode of bean in comparison with 24-epibrassinolide. /Bending in mm/.

concentration /mol/ Substance 10- ⁸ 10’ 10- ¹⁰ ,o- ¹¹ bend in mm 24-epi brassinolide 4.2 4.3 3.0 1/4 formula I,R=NHCH/CHj/ ₂ 3.8 2/5 2/0 2/8 formula I,R=0H 2/6 3.6 4/5 2/3 formula I,R=0CH ₃ 4.4 3.0 2/3 1/4

-5ExampleJ 242 122

Methyl 5ÍSC-^X2SlÍDX--^z-2Íz2ÍtíXá£22ŽzIz222ZÉZ2S2z25fc?Íz2ÍD2£Z §ZÍ*2E2z5^2cholangvé_/formula _I _t _R=OCHj/

6^-Hydroxy-3«< acid methyl ester. _z 5-cyclo-23 _z 24-dinor-5<<-cholanate /formula XV/

3 _- Hydroxy- _23-24 -dinor-5-cholenoic acid methyl ester (formula 11) (4 g) is dissolved in anhydrous pyridine (50 ml) and tosyl chloride (6 g) is added. After three days at room temperature, the mixture is poured onto ice _{, diluted} with water, and the product is filtered off _with suction, washed with water, and shaken into ether. The solution is washed with water _{, NaHCO3} , and water. Drying over sodium sulfate and evaporation of the solvent in vacuo gives a _white crystalline product (formula III). IR spectrum (CCl*): 1738 _z /1435/ _z 1162 cm" ¹ /C00CH3/z 1368z 1189z 1178 cm" ¹ /-SOg-/, 1716 cm" ¹ /CO/. For C30H4 ₂ °5 ^{S /514} ' ^70/ calculated: 6 _Z 28X S; found: 6 _Z 14X S/,.The product is added in the solid state to a boiling solution of sodium acetate /3 _Z 2 g/ and pyridine /20 ml/ in acetone /1 1/ and water /250 ml/ while stirring with a stirrer. Boiling with stirring is maintained for another 2 h 15 min. _then left to stand overnight at room temperature. At max.

At 45° C, most _of the acetone is removed in vacuum, the mixture is poured onto ice _{, diluted} with water and taken up in ether, washed (10 times) _with water.

After evaporation /max. 35 *C/ a crystalline product /4 _Z 2 g/ is obtained. For analysis, the sample is dissolved at room temperature in acetone and allowed to crystallize at -20 °C overnight; mp 127^128 ^e Cz [®<j0 ⁺ 36 /CHClj, c ^a 1z29/. For ^23^36^3 /360.52/ calculated:

76 _Z 62X C _z 1Q _z 07X H; found: 76 _Z 23X C _z 10 _z Q4X H.

6-Oxo-3^ _Z 5-Cyclo- _23Z 24-Dinor-5<*-Cholanic Acid Methyl Ester

The crude 6-hydroxy derivative (formula IV) is dissolved in pyridine (40 ml) and the solution is added at 0°C and with stirring to the CrO^pyridine complex prepared from CrO ₃ (5 g) and pyridine (40 ml). After the addition, stirring is continued for 4 hours at room temperature and left to stand overnight. The mixture is then diluted with ether,

-6242 122 the undissolved portion is filtered off with suction and washed well with ether. The filtrate is washed 10 times with water, dried over Na ₂ S0 ₄ and the solvent is distilled off. Chromatography on silica gel in benzene and benzene-2% ether gives the product /2.2 g/, which after crystallization from methanol gives 1.84 g of the desired substance, mp 112»113 ' *C,ř*J _Ď ⁺ 31 ZCHClj, c « 1.34/. IR spectrum /CCl^/: 1737, 1433, 1161 cm” ¹ /COOCHj/; 1690, 3080, 3020, 3005 cm“ ¹ /carbonyl conj. with cycloprop. ring/. For /35'8.50/ calculated: 77.05% C,

9.56% H; found: 77.28% C, 9.52% H.

3/3-Hydroxy-6-oxo-23,24-dinor-5<-cholanic acid methyl ester /zorec v/

The previous product /500mg/ is heated for 1 h to boiling with acetic acid /18 ml/ and 2N-H ₂ S0 ₄ /3.6 ml/. The mixture is poured onto ice, diluted with water, filtered off with suction and washed with water. The still wet product is rinsed with methanol /50 ml/ into a flask, a solution of ^K 2 ^C0 3 ⁱⁿ 3 ml of water is added, boiled for 45 min.; then acidified with 10% HCl, poured onto ice and filtered off with suction. After washing with water and crystallisation from methanol we obtain 330 mg of product, mp 177ař178°C. IR spectrum /CCl^/: 3620 cm“ ¹ /OH/, 1714 /CO/, 1737, 1161 cm“ ¹ /COOR/.

6-oxo-23,24-dinor-5'\-chol-2-enoic acid methyl ester /formula VI/

The hydroxy derivative /formula V/ /500 mg/ is dissolved in pyridine /10 ml/ and tosyl chloride /750 mg/ is added. Left to stand for 48 h, then ice is added and poured into ice water /150 ml/. After a while, the mixture is filtered off with suction, washed with water, taken up in ether, the solution is washed with water, 5% HCl, water, NaHCO^, and water. After evaporation in vacuo, a white crystalline residue /600 mg/ of tosylate remains, mp 139«.141°C, Kfc“ ^{15 /CHCl} 3' ^{c =} 1.61/. IR-spectrum /CCl4/: 1738, 1162 cm” ¹ /COOCHj/, 1368,1189, 1178 cm ¹ /-S02-/, 1716 cm“ ¹ /CO/.

This product is heated to boiling with LiBr (750 mg) in dimethylformamide (8 ml) under argon for 45 min. After cooling, the mixture is diluted with water and extracted into ether, the solution is washed with water, 5% HCl, water, NaHCO^ and water. The product is freed from more polar impurities by chromatography in a benzene solution on

-7242 122 silica gel /12 g/. In this way 333 mg of crystalline pure fraction is obtained, which on crystallization from methanol gives 300 mg of product VI, mp 148^148.5 ^e C,W _Ď + 27 /CHCtj, c=1.28Z. For ^C 23 ^H 34°3 ^/358 ' ^50/ calculated: 77.05% C, 9.56% H; found:

77.18% C, 9.86% H.

2o<,3e<-dihydroxy-6-oxo-23,24-dinor-5o<choic acid ethyl ester /formula VII/

The unsaturated ester (formula VI) (1 g) is dissolved in tetrahydrofuran (50 ml), 10 ml of water, N-methylmorpholine-N-oxide (1.4 g) and 60 mg of 0s0* dissolved in a few ml of t-butyl alcohol are added. The mixture is stirred for 8 h at room temperature in an argon atmosphere, left to stand overnight, Na ₂ S0 ₃ .7H ₂ 0 (2 g) dissolved in 10 ml of water is added and stirred for 2 h. Then diluted with water and taken up in dichloromethane, washed with 5% HCl, NaHCO^ and water, the solvent is evaporated and crystallized from methanol at +5° C. 630 mg of diol with mp 196<#97.5 ^,£«*1^-6 /CHClj,C * 2.3/ are obtained. IR spectrum /CHClj/: 3620, 3580, 1045, 1010 cm” ¹ /OH/; 1730, 1438, 1170 cm” ¹ /COQCH^/, 1712 /CO/. Chromatography of the mother liquors on silica gel in benzene-methanol /0.75%/ yields another 400 mg of diol. For ^23 ^Η 36θ5 ^ ³ ^2.52/ calculated: 70.37% C, 9.25% H; found: 70.77% C, 9.29% H.

2<*,3<*-diacetoxy-6-oxo-23,24-dinor-5o<-cholanic acid ethyl ester

Diol VII (500 mg) is acetylated in pyridine (5 ml) with acetic anhydride (3 ml) overnight. After pouring onto ice, taking up in ether and washing with water, 5% HCl, NaHCO, and water, the product ^V » is crystallized from methanol to give 530 mg of the substance, mp 206-208-*C,£«3 _O -14 /CHClj, ca 1.84/. IR spectrum /CCl*/: 1740,

1250, 1044 cm” ¹ /OAc/, 1745, 1164 cm” ¹ /COOCHj/, 1719 cm“ ¹ /CO/. For ^C 27 ^H 40°7 ^ ⁷⁶ ^ ⁵⁹ ^ calculated: 68.04% C, 8.46% H; found 68.03% C, 8.25% H.

2*<,3o<-diacetoxy-23,24-dinor-B-homo-7-oxa6-oxo-5<-cholanic acid ethyl ester /formula VIII/

The previous product /446 mg/ is dissolved in dichloromethane /6 ml/

-8242 122 and a solution of trifluoroperacetic acid prepared from /CFjCO/jO /1 ml/ and H ₂ °2 0.15 ml/ in 15 ml of dichloromethane at 0~ *C was added.

Left to stand at room temperature for 5 h. Then washed with water, NaHCO^ and water, dried and evaporated. Crystallization from methanol gives compound VIII /383 mg/, mp 2654(267 ^e C,W0 + 34 /CHClj, c ~ 1.28/. IR spectrum /CHCL3/s /CO/: 1732 cm“ ¹ /C00CH3, OAc, lactone/; 1435, 1170 cm' ¹ /COOCH ₃ /, 1252, 1045 cm“ ¹ /OAc/,

1183 cm' ¹ /lactone/. For ^c 27 ^H 40°8 /492.59/ calculated: 65.83% C, 8.19% H; found: 66.37% C, 8.15% H.

2<<, 3<**-dihydroxy-7-oxa-6-oxo-23, 24-dinorB-homo-5o<-cholanic acid methyl ester /formula I, R - OCHj/

A solution of diacetate /formula VIII/ /150 mg/, KHC0 ₃ /120 mg/ in methanol /30 ml/ and water /1 ml/ is boiled for 30 min., then acidified with 5% HCl, concentrated in vacuo to a small volume, water is added and the product is taken up in ether. After washing with water, it is evaporated and the residue /110 mg/ is crystallized from a heptane-methanol mixture. The product /81 mg/ melts at 185*186 *C.íp<1 _ï + 32 /CHCl ₃ , c = 1.40/. IC- spectrum /CHCl ₃ /: 3610, 1050 cm“ ¹ /OH/, 1723, 1435, 1170 cm“ ¹ /lactone/.

For C ₂ 3 ^H 36°6 /*08/52/ calculated: 67.62% C, 8.88% H; found: 67.86% C, 8.90 H.

Example 2. 3»><-dihydroxy-7-oxa-6-oxo-23,24-dinorB-homo-5o<-cholanic acid /formula I, R = OH/

A solution of the ester of formula VIII /500 mg/ and NaOH /800 mg/ in ethanol /26 ml/ and water /9.5 ml/ is heated to boiling in an argon atmosphere for 37 h. Then acidified with HCl, concentrated on an evaporator to a third of the volume, diluted with five times the volume of water and left to stand overnight. The precipitated crystals are filtered off with suction /400 mg/, mp 305£310 *C. Crystallization from aqueous ethanol gives the product /303 mg, mp 317*319 ^e C, uniform in chromatography even on a thin layer of silica gel in the system CHCl ₃ /9/, MeOH /0.5/ and AcOH /0.5/. For ¢2^^0^/394.49/ calculated: 66.98% C, 8.69% H; found: 67.05% C, 8.83% H.

-9242 122

Př - i--llt-Z-lS SiÍÍX ÍE£2EXÍšS£££.!!!X§£lÍ2X_ Z-ZÉ Í&XS!£2*XZ

Iz2£2ZÉz2i2Z--€--Z-ÍD2£z5ztl222Z^Z;£!22Í 522ϊέ-£ϊ£2£££.ίΑ-£-ζ_ 2S^£S3Ó£í!é£t!3Í2-Acid li na 2«,3«<-di acetoxy-7-oxa-6-oxo-23,24-di nor-B-homo-5<x.cholan

The dihydroxy acid /formula I, R » OH/ /300 mg/ is acetylated in pyridine /12 ml/ with acetic anhydride /5 ml/ overnight. Then water /5 ml/ is added to the mixture and heated for 1 h at 90° C. Then diluted with water and acidified with HCl. Crystals are separated, which are filtered off after 5 min. The yield is 338 mg, mp 266*268 °C. Crystallization from aqueous acetic acid gives a pure substance /320 mg/ with mp 271^273.5 + 26 /CHClj, c « 1.53/. IR spectrum /CHCl^/j 3500-2500, 1711 cm ¹ /COOH/, 1740, 1256 cm ¹ /OAc/, 1730, 1186 cm ¹ /lactone/. For ^C 26 ^H 38°8 7478.56/ calculated: 65.25% C, 8.00% H; found:

65.42% C, 8.13% H.

0-1,2-Dimethylpropyl ester

2e<,3o<-diacetoxy-7-oxa-6-oxo-23, 24-di nor-B-homo-5c<cholanic acid /290 mg/ is azeotropically dried by concentrating its benzene solution /40 ml/ to 15 ml, adding oxalyl chloride /1.2 ml/ and leaving to stand for 3 h, then adding a drop of pyridine and after another 2 h evaporating in vacuo /temperature up to 35 ”0/ to dryness. The crystalline residue is freed from oxalyl chloride residues by repeated addition of dry benzene and its distillation in vacuo /up to 35 »C/ to dryness. The chloride thus prepared is dissolved in 3 ml of benzene and adding 0-3-methyl-butanol-2 /0.2 ml/. Leaving to stand overnight, worked up by taking it up in ether, washing with NaHCO^ solution, water and chromatographed on silica gel /20 g/ in benzene-ether /10%/, separating the crystalline ester /246 mg/ from a small amount of polar impurity. Crystallization from methanol gives the pure substance /196 mg/, m.p. t, 240*241 °0,ί<<^+ 35 /CHClj, c = 1.33/. IR spectrum /CHCl^/: 1736,1256,1050 cm ¹ /OAc/, 1726, 1184 cm ¹ /COO/. Mass spectrum: M ⁺ = 548.

For C ₃₁ H _4g 0g _/548/69/ calculated: 67.85% C, 8.82% H: found: 68.16% C, 8.80% H.

-10242 122

0-1 ₁ 2-Diniethy lpropytester of 2<*,3«<>-dihydroxy-7-oxa-6oxo-23,24-dinor-B-homo-5o<-cholanic acid /formula 1, R « OCH /ch ₃ /ch/ch ₃ / ₂ /

The previous product /D-1,2-dimethylpropyl ester of 2o<,3o<diacet-oxy-7-oxa-6-oxo-23,24 -dinor-B-homo-5ck ^_ cholanic acid/ /150 mg/ is heated to boiling in an aqueous /1 ml/ ethanolic /30 ml/ solution in the presence of KHCO^ /120 mg/. After 30 minutes the mixture is acidified with HCl, concentrated almost to dryness, diluted with water and taken up in ether. After washing the solution with water and NaHCO^ and drying with Na ₂ S0* the solvent is evaporated in vacuo and the residue /128 mg/ is recrystallized successively from benzene-heptane and methanol-heptane. It gives 101 mg of ester with mp 215<215.5 ^e C,í*<J _D + 38 /CHCl^, c 1.63/. IR spectrum /CHCl^/: 3610,3585,1027,1040, 1067 cm ¹ /OH/, 1721, 1183 cm” ¹ /C00/. For ^C 27 ^H 44°6 ^*^4.62/ calculated 69.79% C, 9.55% H; found: 70.03% C, 9.52% H.

£íl£l2ï.As.-ŮSÍ4.£X2£lÍ22..žťfc3^zďí!!Xy£22¥zZz2S2ZŠZ2&2ZŠ££Ž£z.. ^ÍQ2£zSz!!2!2Z^Z£!!2l2Q2y é.Í£S2££ S.ít.B - Ζ-ϋΰ 2Amide of 2<*,3o<r-diacetoxy-7-oxa-6-oxo-23,24-di nor-B-homo5o<rc holanic acid

From 2ot,3c<-diacetoxy-7-oxa-6-oxo-23,24-dinor-B-homo5c4.-cholanic acid (157 mg) the chloride was prepared according to the procedure given in Example 3, dissolved in benzene (15 ml) and dry ammonia was bubbled through the solution through a frit for 5 min. After standing overnight it was diluted with benzene containing several percent chloroform and ethyl acetate. After washing with H^O, HCl, NaHCOj and HgO and evaporation, a crystalline residue (110 mg) appeared m. p. 308^310 °C.

IR spectrum /CHCl ₃ /: 3530, 3415, 1684,1591 cm ^-1 /CONH ₂ /;

1739, 1255 cm" ¹ /OAc/; 1729, 1189 cm" ¹ /lactone/.

2o<,3o<-dihydroxy-7-oxa-6-oxo-23,24-dinor-B-homo5o(-cholanic acid amide

To the previous product (100 mg) was added KHCO^ (80 mg) dissolved in water (1 ml) and the mixture was heated to boiling for 30 min after addition of methanol (25 ml). Concentration of the reaction mixture and acidification

242 122

HCt gave the product (76 mg), which after crystallization from ethanol gave a substance with mp 341-343 ^° C (dec.) (57 mg). LC spectrum (KBr): 1679, 1634, 1621 cm- ¹ (CONHj), 1056, 1029 cm- ^{1 (} OH),

1722, 1184 /lactone/. For & ₂ 2 ^Η 35 ^{Ν0 /393} ' ^51/ calculated: 67.14% C, 8.96% H, 3.56% N; found: 67.12% C, 8.73% H, 3.59%*N.

xdinor-B-homo-Síjíj-c ho lanová^/ vz rec _- l _£- R_» _w NHCjHg/

2<*,3o4-Diacetoxy-7-oxa-6-oxo-23,24-dinor-Bhoao-Set-cholanic acid ethylamide

From 2<*,3<And1aeethoxy-7-oxa- 6-oxo-23,24-dinor-B-homo5t<-cholanic acid (157 mg) the chloride was prepared according to the procedure given in Example 3, dissolved in benzene (15 ml) and 1 ml of a benzene solution containing 50% ethylamine was added. The mixture was left to stand overnight. Then diluted with benzene, washed with H^O, HCl (5%) and NaHCO-j. After evaporation in vacuo, a crystalline product was obtained (146 mg), mp 289<290 *C. ΐί-spectrum» (CHCl2): 1740,1252 cm“ ¹ (OAc); 1740,1189 cm' ¹ (lektor^ 3455, 1763, 1521 cm' ¹ (CONH).

Ethylamld 2"**3<A-diNydroxy-7-oxa-6"0xo~23,24-dinor-Bhomo-5A-cholanic acid /formula I, R » NHC^lij/

To the previous product (138 mg) was added KHCO^ (120 mg) dissolved in water (1 ml), then methanol (30 ml) and the mixture was heated to boiling for 30 min. After concentration to one quarter, the volume was made up to the original volume with water and acidified with two drops of conc. HCl. Reconcentration gave the product (105 mg); crystallization from methanol-ether gave the substance (70 mg), m.p. t, 301£303 ®C. X-ray spectrum (CHCl-j): 1720 cm“ ¹ (lactone); 3450, 1668, 1658,

1520 cm“ ¹ /CONH/; 3625, 3585 cm“ ¹ /OH/. For C ₂₄ H ₃₉ N0 ₅ /421.56/ calculated: 88.37% C, 9.32% H, 3.32% M; found: 68.49% C,

9.26% H, 3.28% N.

«ííiSi2É_Éi-l52E£2EZl25Í^_ÉX2®j:Í2Z_.2o< _t 3o<2di h2^£2čXzIz225zá2č2z« 25Α21ζ2ίΰ2£ζ5ζ!!252ζ5^ζ£ΐ!2ΐ2ΰ2ϊ2.£ϊ£2£££-Ι<-£_ζ-ϋί!£ίίί £^362-Z 2cx,3o<-diacetoxy-7-oxa-6-oxo-23,24-dinor-B-homo5<<-cholanic acid /227 mg/ was prepared according to the procedure described in Example 3

-12242 122 prepared chloride, dissolved in anhydrous benzene /10 «1/ and added 2-aminopropane /0.5 ml/. After 15 h. diluted with benzene, washed with water, HCl /5%/, NaHCOj, water, concentrated to a small volume and added ether. A crystalline amide with mp 321«322 »C is precipitated in a yield of 155 mg,{><.] ₀ +25 /CHCl ₃ , c = 1.66/. Another portion /65 mg/ with the same mp, was obtained similarly from the mother liquors. IR spectrum /CHClj/: 3440, 1661, 1514 cm” ¹ /CONH/; 1736, 1252, 1052 cm ¹ /OAc/; 1736, 1189 cm ¹ /lactone/. For C ₂₉ H ₄₅ N0 _? /519.66/ calculated: 67.02% C, 8.73% H, 2.69% N; found: 66.93% C, 8.96% H,

2.67% N.

Isopropylamide of 2o4,3x,-dihydroxy-7-oxa-6-oxo-23,24-dinorB-homo-5°<>-cholanic acid /formula I, R « NHCH/CH^/^ /

The previous product /135 mg/ and KHCO^ /110 mg/ dissolved in 1 ml of water were heated to boiling for 35 min after adding methanol /25 ml/. After concentration, water was added and concentrated again. 50 mg crystallized and by repeating the procedure another 46 mg of product. Crystallization from methanol-ether gave 91 mg, mp 325<326°C, + 34 /CHClj, c = 1.28/. IR spectrum /CHClj/: 3440, 1660,

1517 cm ¹ /NHCO/; 1722, 1186 cm ¹ /lactone'; 3620, 3585, 1027cm ¹ /OH/. For C ₂₅ H ₄₁ NO ₅ /435.59/ calculated: 68.92% C, 9.49% H,

3.22% N; found: 69.15% C, 9.58% H, 3.48% N.

P Č 22ŘÍÍ í2 SÍSLiSZ ššlTSX 23 El §z!i2E ££2ΐ2!22ϊ SSg ---- - 3 - 2 - I sobuty lam i d 2®<,3<A-diacetoxy-7-oxa-Ó-oxo-23,24-dinorB-homo-5c<-ch o lanic acid

From 2es,3o<-diacetoxy-7-oxa-6~oxo-23,24-dinor-B-homo5o<-cholanic acid /245 mg/ the chloride was prepared according to the procedure given in Example 3, it was dissolved in dry benzene 710 ml/ and isobutylamine /0.5 ml/ was added. The next day it was diluted with benzene and washed with H^O, HCl /5%/, NaHCO^ and H^O. The solution was concentrated to a small volume and a double volume of ether was added. The substance crystallized /187 mg/, mp 298£300°C and from the mother liquors with the same procedure another 39 mg with mp 295<#298 **C were obtained. Recrystallization from benzene-ether gave 177 mg of product, mp 300-301.5° C. and 29 mg, mp 275-297 °C, M ₀ + 34 (CHCl 3 ), c ≤ 1.28.

-13242 122

IR-Spectrum /CHClj/: 1740. 1253 cm“ ¹ /OAc/; 3455.1666. 1523 cm“ ¹ /CONH/. 1730 infl. ,. 1188 cm“ ¹ /lactone/. For ε _3θ Η ₄₇ ΝΟ _? /533.69/ calculated: 67.51X C. 8.89% H. 2.62% N; found: 67.12% C.

9.11% H. 2.48% N.

2°<.3©<-dihydroxy-7-oxa-6-oxo-23 acid isobutylamide. 24-dinorB-homo-5o<-cholanate /formula I. R = NHCH^CH/CH^/g /

A solution of KHCOj /150 mg/ in water /1 ml/ is added to the previous product /170 dg/. then methanol /35 ml/ and the mixture is heated to boiling for 30 min. Then concentrated to one quarter of the volume and four times water is added. The product crystallizes overnight and by concentrating the mother liquors another is obtained. Both are combined /115 mg/, mp 291<293 °C. Recrystallized from methanol-ether gives the amide /83 mg/, mp 297&298.5 *C,[°0 _D + 19 /CHCl ₃ . c = 1.34/. ΐδ-spectrum /CHClj/: 3455. 1661. 1526 cm” ¹ /CONH/; 1721.

1185 cm" ¹ /C00/; 3620. 3570. 3370. 1067 cm ¹ /OH/. For C ₂ 6 ^H 43 ^N0 5 /449.61/ calculated: 69.45% C. 9.82% H. 2.91% N.

Claims (2)

SUBJECT MATTER 242 122 Analogs (1) wherein R is OX or NHX, wherein X is H or alkyl of 1 to 6 carbon atoms. 2. A process for the preparation of brasinolide analogues according to claim 1, characterized in that the methyl 3-β-hydroxy-23,24-dinor-5-cholenoic acid methyl ester (formula II) is converted to the tosyl chloride of formula III by treatment with tosyl chloride. TsO / 111 / -15242 122 this is converted in the alkali metal acetate or pyridine medium to the 6H-hydroxy-3e, 5 &apos; -cyclosteroid of formula IV, (IV) > which after oxidation to ketone is converted in an acidic environment at the 3--hydroxyderivát V / V / ob ^^ and ^^ J ^ 3; lch os ^ | ^ grid _{that it} cleaving ester toluene sulfonic lithium bromide in dimethylformamide to give compound of formula VI, which, by treatment with osmium tetroxide in the presence of N-methylmorpholine-N-oxide, gives a compound of formula VII, cooch ₃ 242 122 (VII) and this is acetylated to the diacetate which is converted to the lactone of formula VIII by the action of a peracid, preferably trifluoroacetic acid or permeation, which, after saponification and acetylation, reacts with oxalyl chloride to provide the corresponding chloride (s) with NH3, amines or alcohols having 1-6 carbon atoms, followed by partial saponification to give the final product.