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1.
The reaction of pregnenolone and 3,5-cyclo-5-pregnan-6-ol-20-one with trifluoroperacetic acid produces the trifluoroacetates, hydrolysis of which gives the 3,5alpha;,6-triol.  相似文献   

2.
Lutfun Nahar  Alan B Turner 《Tetrahedron》2003,59(43):8623-8628
Evidence for the presence of 3β,6α-dihydroxy-5α-chol-9(11)-en-23-one in the aglycone mixture from the starfish Marthasterias glacialis is provided by the synthesis of 3β,6α-dihydroxy-5α-cholan-23-one (19) and its identification in the hydrogenated aglycone mixture. The side-chain is constructed from the 23,24-dinorcholanol (13) by reaction of the 22-tosylate (16) with the acetylide anion, followed by hydration of the resulting 23-yne (17).  相似文献   

3.
4.
The 3-O-β-D-galactopyranosyl-20-O-β-D-glucopyranoside and 3-O-β-D-glucopyranosyl-20-O-β-Dgalactopyranoside of 3β,20S-dihydroxydammar-24-en-12-one, which are structural analogs of chikusetsusaponin-LT8 (1), a minor glycoside from Panax japonicus, were synthesized for the first time.  相似文献   

5.
Aliphatic polycarbonates and their copolymers have been used in drug controlled release system and other biomedical applications due to their good biocompatibility, favorable mechanical properties and some elasticity1, such as poly(1, 3-dioxan-2-one)2 and…  相似文献   

6.
Novel polycarbonates from 5-allyloxy-1, 3-dioxan-2-one (ATMC) with 5, 5-dimethyl- 1, 3-dioxan-2-one (DTC) were successfully synthesized for the first time using immobilized porcine pancreas lipase (IPPL) as catalyst. The resulting copolymers were characterized by IR, ^1H NMR, ^13C NMR and GPC. The molecular weight (Mn) of the copolymer with molar feed ratio of 10:90 (ATMC:DTC) was 9300 and the polydispersity was 1.31, while the Mn increased to 14300 and polydispersity of 1.25 with the feed ratio of 50:50. Moreover, the composition of the copolymers agreed well with the monomer feed.  相似文献   

7.
Reduction of 17-hydroxyprogesterone (1) with NaBH 4 produces 17,20-dihydroxypregn-4-en-3-one (2) and pregn-4-en-3,17,20-triol (3)  相似文献   

8.
New esters of 3β,5α,6β-trihydroxysteroids and 3β,5-dihydroxy-6-ketosteroids containing 6-chloropyridine groups characteristic of the alkaloid epibatidine were synthesized by acylation with 6-chloronicotinoylchloride. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 175-179, March-April, 2009.  相似文献   

9.
Abstract: The synthesis of 5-iodo-5α-cholestan-6-one (6), its 3β-acetoxy-(7) and 3β-chloro-(8) analogues, 3β-acetoxy-5-iodo-5α-stigmastan-6-one (9) and its 3β-chloro-(10) analogue by the reacion of silver chromate-iodine and pyridine with the corresponding steroidal olefins (1-5) is described. The structures of these products have been established on the basis of their elemental, analytical and spectral data.  相似文献   

10.
Cholesterol (1) is used to synthesize again 5-hydroxy-2,7-dien-6-one (5) through the intermediates 2-4. cis-Hydroxylation of 5 with OsO 4 and subsequent acetylation give steroids 6-8. Dehydration of 5-hydroxy-6-ketone 6 forms the unsaturated compounds 9-11  相似文献   

11.
12.
New steroid derivatives containing 6-chloropyridine groups characteristic of the alkaloid epibatidine and neonicotinoid insecticides were synthesized by reacting 3β,5α,6β-trihydroxysteroids or 3β,5-dihydroxy-6ketosteroids with 2-chloro-5-chloromethylpyridine. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 180-182, March-April, 2009.  相似文献   

13.
The synthesis of a plant growth promoter furostanol which bears the characteristic functionality of teasterone on rings A and B is described.

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14.
20-Hydroxy-20-(4,5-dihydroisoxazol-5-yl) steroid was brought into reactions typical of functionalization of rings A and B in ecdysteroids. The dihydroisoxazole ring remained unchanged in reactions leading to formation of the 2,3-dihydroxy-6-oxo moiety. The isomerization of 5-bromo derivative in acetic acid in the presence of a catalytic amount of hydrobromic acid and Lewis acids is accompanied by elimination of the hydroxy group from C20 and subsequent migration of the double bond to the heteroring to afford the corresponding isoxazole derivative.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 10, 2004, pp. 1500–1505.Original Russian Text Copyright © 2004 by Litvinovskaya, Drach, Khripach.  相似文献   

15.
An ecdysteroid analog has been synthesized from -sitosterol.Institute of Bioorganic Chemistry, National Academy of Sciences of Belarus', 220141, Belarus', Minsk, ul. Akad. Kuprevich, 5/2. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 488–491, July–August, 1999.  相似文献   

16.
Zusammenfassung Die Synthese von 3, 16-Diacetoxy-5 -pregnan-20-on (VI) aus 3-Acetoxy-5 -pregn-16-en-20-on und eine verbesserte Darstellung von 3, 16-Diacetoxy-5 -pregnan-20-on (III) aus 3-Acetoxy-pregna-5, 16-dien-20-on werden beschrieben.  相似文献   

17.
The natural compound (24R)-3-hydroxystigmast-5-en-7-one has been synthesized from -sitosterol.Institute of Bioorganic Chemistry, National Academy of Sciences of Belarus', 220141, Belarus', Minsk. Ul. Akad. Kuprevicha, 5/2. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 484–487, July–August, 1999.  相似文献   

18.
Eudesmane and agarofuran are naturally occurring sesquiterpenoids with characteristic decalin skeletons. These natural products frequently contain multiple hydroxyl groups and contiguous stereocenters. Members from these families show cytotoxic, immuno- s…  相似文献   

19.
Russian Chemical Bulletin - A new approach to the synthesis of isomeric 19-hydroxypregn-4-en-20-one (1) and 19-hydroxy-5β-pregn-3-en-20-one (2), the selective ligands of membrane progesterone...  相似文献   

20.
以脱氢表雄酮为原料,经羟基乙酰化,羰基亚乙二氧基化,CrO3/3,5-二甲基吡啶氧化,硼氢化钠还原,脱17-位亚乙二氧基,脱3-位乙酰基,用叔丁基二甲基氯硅烷(TBDMSC1)保护3,7-OH,17-位环氧化,17-位开环,脱TBDMSC1保护等十步反应合成了四个新型的17α-乙炔基-5-雄甾烯-3β,7β,17β-三醇(HE3286)衍生物,其结构经1H NMR和MS表征.  相似文献   

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