73890-91-2

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• 73890-93-4 3-Methoxy-14α,15α-methylen-oestra-1,3,5(10)-trien-17-on 

Relevant academic research and scientific papers

Intramolecular vs. intermolecular induction in the diastereoselective catalytic reduction of 17-oxo-steroids

The asymmetric reduction of enantiomerically pure steroid ketones was carried out by using oxazaborolidine catalysts with a variety of achiral or chiral ligands. The efficiency of chiral ligands (1,2-amino alcohols) as well as the effect of the stereogenic centers in the substrate on the catalytic asymmetric reduction were studied. It was found that the diastereoselectivity is mainly controlled by the absolute configuration of the chiral ligand. The reduction gave either the 17α- or 17β-alcohol with high diastereomeric purity. This catalytic reduction represents a very practical solution to the problem of controlling C(17)-stereochemistry in synthesis of steroid compounds.

A novel synthesis of 14α,15α-methylene estradiol (J 824)

A novel approach to the synthesis of the orally active estrogen 14α,15α-methylene estradiol (8, J 824) is described, starting with 3-methoxy-estra-1,3,5(10),8,14-pentaen-17α-ol (5).The 14α,15α-methylene bridge was sonochemically introduced by regioselective and stereoselective Simmons-Smith methylenation of the 14-double bond.Birch reduction of the 8-double bond provided the desired 8β-H,9α-H steroid, whereas ionic hydrogenation afforded the 8β-H,9β-H isomer, together with an epimerization of the 17α-hydroxy group.Oxidation of the Birch product yielded the corresponding 17-oxo steroid, which gave the title compound by diborane reduction.For radioimmunoassay development the 6-(O-carboxymethyl)-oximino derivative of 8 was prepared as hapten and the 2-hydroxy derivative of 8 was synthesized as a potential metabolite of 8, and 8 was tritium labeled as well. - Keywords: estrogens; 14α,15α-methylene estradiol; steroid synthesis; hapten; tritium labeling

Synthesis, Reactivity and 1H-NMR-Spectroscopy of 14,15-Methylene Derivatives of the Androstane and Estratriene Series

Under the activating and syn-directing effect of the 17-hydroxy group the Simmons Smith cyclopropanation of 14,15-unsaturated 17-hydroxy steroids of the androstane and estratriene series 1a, 5 and 9 affords the 14,15-methylene steroids 2a, 6 and 10 with cis position of the 14,15-methylene and 17-hydroxy groups in a stereospecific reaction.Oxidation of these compounds yields the 17-keto derivatives 3, 7 and 11, which were reduced to the compounds 4a, 8 and 12 with trans position of the 14,15-methylene and 17-hydroxy groups by complex hydrides or diborane.In a phase transfer catalyzed reaction dichloro- or dibromocarbene was added to 3β,17β-diacetoxy-5α-androst-14-ene 1b forming the 14β,15β-dihalogenmethylene steroids 13 and 14.The 17-keto steroids 7 and 11 were transformed into 17-methyl and 17-ethynyl derivatives 15-20.Cleavage of the cyclopropane ring of 2a, 2b and 3 by catalytic hydrogenation affords the 14β-methyl derivatives 21-23, the acid catalyzed ring opening with hydrogen chloride yields the 14β-chloro, 15β-methyl derivatives 24-29.Structure elucidation has been established by 1H n.m.r. and mass spectroscopy.The configuration at C17, C14 and C15 was also determined by means of 1H n.m.r. spectroscopy, using the chemical shifts of the 18-protons, the coupling constants and the chemical shifts of the 17-protons.The configuration of the 17-disubstituted steroids was established with the aid of an europium shift reagent.

14,15-Methylene derivatives of the estrane series and methods for preparing same

Compounds of the general formula STR1 in which R' is hydrogen or a methyl radical; R is a hydroxyl, acetoxy, arylaminocarbonyloxy, alkylaminocarbonyloxy radical; Z is hydrogen or a lower alkyl, or R and Z together are oxygen. These compounds exhibit a very favorable separation of desirable contraceptive and undesirable uterine and antigonadotrophic properties.