Methyl Steroids. Studies on the Synthesis of 4-Methyl- and 4,4-Dimethyl-25-hydroxycholestan-3-one Derivatives

2007 ◽  
Vol 72 (10) ◽  
pp. 1319-1330 ◽  
Author(s):  
Iwona Skiera ◽  
Zdzisław Paryzek
Keyword(s):  
Vitamin D ◽  
Enol Acetate ◽  
Synthetic Routes ◽  
Reaction Formation ◽  
Oxo Compounds ◽  
Derivatives Of

The synthetic routes to 25-hydroxy derivatives of 4-methylcholest-4-ene and 4,4-dimethylcholest-5-ene from methyl lithocholate and methyl 3β-acetoxy-24-homochol-5-en-25-oate (6) have been investigated. The cholest-5-ene-3β,25-diol (7), readily available from 6, was transformed in a few steps into the title compounds. It was also found that bromination of 24-acetoxy-5β-cholan-3-one (1) and of its enol acetate followed by dehydrobromination is not a regioselective reaction. Formation of mixtures of 2β-bromo-3-oxo and 4β-bromo-3-oxo compounds, which gave mixtures of 24-acetoxychol-4-en-3-one (4) and 24-acetoxy-5β-chol-1-en-3-one (5) of similar polarity was observed. 4-Methyl-25-hydroxycholest-4-en-3-one (14) and 4-methyl-25-hydroxycholesta-1,4-dien-3-one (16) are potential substrates for the preparation of 4-methyl analogs of vitamin D3.

FOLLOW-UP OF LONG-TERM TREATMENT OF PREDIALYSIS RENAL BONE DISEASE WITH 1-α-HYDROXY-DERIVATIVES OF VITAMIN D

1983 ◽  
pp. 511-516
Author(s):  
J.R. JUTTMANN ◽  
D.H. BIRKENHÄGER-FRENKEL ◽  
T.J. VISSER ◽  
C. VAN KRIMPEN ◽  
J.C. BIRKENHÄGER
Keyword(s):  
Vitamin D ◽  
Bone Disease ◽  
Term Treatment ◽  
Long Term Treatment ◽  
Renal Bone Disease ◽  
Derivatives Of

Synthesen von TRH-Derivaten des Typs L-Pyr-L-His-L-Pro-NH-(CH2)n-NHa (n = 4, 7,10).

1976 ◽  
Vol 31 (10) ◽  
pp. 1410-1415 ◽  
Author(s):  
Stefan Fuchs ◽  
Wolfgang Voelter
Keyword(s):  
General Structure ◽  
Biologically Active ◽  
New Class ◽  
Synthetic Routes ◽  
Derivatives Of

Synthetic routes to a new class of biologically active TRH derivatives of the general structure L—Pyr—L—His—L—Pro—NH—(CH2E)n—NH2 are described.

Vitamin D relatives. Part I. B-thiophene-des-A-cholestanes. Solvolytic reactions of some derivatives of 2,2-disubstituted cyclohexane-1,4-diol and 4-hydroxycyclohexan-1-one

1986 ◽  
Vol 64 (8) ◽  
pp. 1536-1539 ◽  
Author(s):  
Jacek W. Morzycki
Keyword(s):  
Vitamin D ◽  
Thiophene Ring ◽  
Derivatives Of

Some derivatives of des-A-cholestane with a thiophene ring B have been prepared from triketone 2. The reactions of tosylates of C-10 alcohols (7b, 9b, and 8c) leading to A-ring ethers (10 and 11) and olefin 5, respectively, have been studied. The solvolysis of tosylate 4c and the Bamford–Stevens reactions of p-tosylhydrazones 3c and 13b are also discussed.

New synthetic routes to B-halogenated derivatives of cobalt dicarbollide

1995 ◽  
Vol 34 (21) ◽  
pp. 5215-5219 ◽  
Author(s):  
Paul K. Hurlburt ◽  
Rebecca L. Miller ◽  
Kent D. Abney ◽  
Trudi M. Foreman ◽  
Raymond J. Butcher ◽  
...  
Keyword(s):  
Synthetic Routes ◽  
Derivatives Of

Synthetic plant growth regulators. The synthesis of C-o-Carboxyphenyl derivatives of some five-membered heterocycles

1977 ◽  
Vol 30 (10) ◽  
pp. 2225 ◽  
Author(s):  
RLN Harris ◽  
JL Huppatz
Keyword(s):  
Plant Growth ◽  
Benzoic Acid ◽  
Plant Growth Regulators ◽  
Growth Regulators ◽  
Heterocyclic Compounds ◽  
Synthetic Routes ◽  
Chloro Derivatives ◽  
Derivatives Of

Synthetic routes to o-carboxyphenyl derivatives of certain heterocyclic compounds, required for testing as plant growth regulators, were investigated. The preparation of 2-(5-phenyl-1,3,4-oxadiazol-2- yl)benzoic acid (3), 2-(5-phenyl-1,3,4-thiadiazol-2-yl)benzoic acid (4), 2-(5-phenyl-1H-1,2,4-triazol-3-yl)benzoic acid (5), 2-(3-phenyl- 1,2,4-oxadiazol-5-yl)benzoic acid (6), 2-(2-phenylthiazol-4-yl)benzoic acid (7), 2-(3-phenylisoxazol-5-yl)benzoic acid (8), 2-(5- phenylisoxazol-3-yl)benzoic acid (9) and chloro derivatives of (3), (4), (8) and (9) is described.

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