23549-24-8Relevant articles and documents
Reactivity of steroidal 1-azadienes toward enamines: an approach to novel chiral penta- And hexacyclic steroids
Lopes, Susana M. M.,Santos, Joana R. C.,Pinho e Melo, Teresa M. V. D.
, p. 1122 - 1132 (2021/02/16)
The chemical behavior of steroidalN-sulfonyl-1-azadienes toward carbonyl compounds, in the presence of pyrrolidine, is described. With aldehydes, these azadienes participate in hetero-Diels-Alder reactions with thein situgenerated enamines. The stereoselectivity results from the approach of the dienophiles from the less hindered α-face of the steroid, with the pyrrolidine moietyendoand retention of the enaminetransgeometry. This diastereoselective synthetic methodology led to a new class of chiral pentacyclic steroids. Interestingly, the studied steroidal scaffolds follow a different mechanistic pathway with cyclic ketones. They undergo a diastereoselective annulation reaction, under enamine catalysis, affording chiral hexacyclic steroids.
Synthesis and evaluation of some novel pregnane derivatives as anti-hyperlipidemic and anti-oxidant agents
Sethi, Arun,Bhatia, Akriti,Singh, Ranvijay Pratap,Srivastava, Atul
, p. 40 - 49 (2019/05/06)
In the present paper, synthesis of few novel pregnane derivatives and their evaluation as potential anti-hyperlipidemic and anti-oxidant agents has been reported. The synthesis of 3β-hydroxy-16α-methoxy pregn-5-en-20-one (4) was achieved by reaction of 3β-hydroxy-5,16-pregnadiene-20-one (3) with KOH/MeOH under reflux. Compound 4 on treatment with succinic and phthalic anhydride afforded compound 6 and 7, respectively. The reaction of the C-20-oxime-pregnadiene (8) with 1,5-dibromohexane yielded 20-(O-6-bromo hexyl)-oximino-3β-hydroxy-pregn-5, 16-diene (9). A novel heterocyclic derivative 3β-hydroxy-androst-5-en [17,16-c]-2′-methyl-7′ bromo-3′,4′-dihydro quinoline (16) was synthesized by reaction of 3 with 3-bromoaniline. However, attempted synthesis of other heterocyclic derivatives by reaction of (3) with other halogenated amine led to Aza-Michael addition products (10-14). The synthesized compounds were also evaluated for their anti-hyperlipidemic and anti-oxidant activities. Compounds 6 and 14 were found to exhibit more lipid lowering and antioxidant activities in comparison to other compounds.
Reactivity of Steroidal 1-Azadienes toward Carbonyl Compounds under Enamine Catalysis: Chiral Penta- and Hexacyclic Steroids
Lopes, Susana M. M.,Gomes, Clara S. B.,Pinho Melo, Teresa M.V.D.E.
, p. 4332 - 4336 (2018/07/29)
The synthesis and reactivity of a steroidal N-sulfonyl-1-azadiene, derived from 16-dehydropregnenolone acetate, toward carbonyl compounds under enamine catalysis is disclosed. An unexpected annulation reaction was observed involving an initial stereoselec
