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Lipase-catalysed deacetylation of androstane and pregnane derivatives: Influence of ring D substitution
(Elsevier Science, 2004-06)
A series of acetoxy derivatives of androstane and pregnane was deacetylated in organic solvents by microbial lipases. The best results were obtained with lipase from Candida antarctica (CAL B), Candida rugosa (CRL) and ...
An efficient enzymatic preparation of 20-pregnane succinates: chemoenzymatic synthesis of 20β-hemisuccinyloxy-5αH-pregnan-3-one
(Pergamon-Elsevier Science Ltd, 2008-02)
Lipase-catalyzed transesterification of the 20 hydroxyl group in a series of pregnanes afforded novel 20-ethyl succinates that are not possible to prepare following the traditional synthetic methods. The reaction is ...
PhI=Nses mediated aziridination of 11-pregnane derivatives synthesis of an 11, 12-aziridino analogue of neuroactive steroids
(2003)
Reaction of 11-pregnene-3,20-dione (6) or 3-α-acetoxy-11-pregnen-20-one (12) with trimethylsilylethanesulfonyl (‘Ses’) iminoiodinane 5 in the presence of copper (I) triflate gave the corresponding α,α-11,12-aziridino ...
Synthesis of 6,19-sulfamidate bridged pregnanes
(American Chemical Society, 2005-10)
Conformationally restrained substituted pregnane-20-one derivatives were obtained by an intramolecular nitrene addition onto a C-5/C-6 double bond involving a tethered C-19 sulfamoyl moiety. The resulting aziridine underwent ...
Microwave assisted preparation of C(1)?C(11) oxygen-bridged pregnanes
(Royal Society of Chemistry, 2011-08)
A procedure for the synthesis of 6,19-cyclopregnanes is described involving an intramolecular alkylation reaction of Δ4-3-keto steroids with a 19-mesylate in the presence of KOH in isopropanol. Three 6,19-cyclopregnanes ...
Allopregnanolone (3α-Hydroxy-5α-pregnan-20-one) derivatives with a polar chain in position 16α: Synthesis and activity
(American Chemical Society, 2009-04)
The lipophilic nature of allopregnanolone prevents its user-friendly application in human medicine. On inspiration by pReviously prepared allopregnanolone with a 16α -bound tetraethylammonium salt, an attempt was made to ...
Propuesta metodológica para la implementación de tres rituales mapuches en la enseñanza básica, subsector artes musicales
(Chile Universidad Mayor, 2006)
El presente seminario, responde a una problemática de identidad, reacciona a la intolerancia de un país que, si bien ha adquirido cierta notoriedad en el mundo por el éxito de su economía, todavía se encuentra en un proceso ...