2Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky pr. 47, 117913 Moscow, Russia; fax: (499) 135-5328; E-mail: email@example.com
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Received May 17, 2013
The interactions between E- and Z-isomers of 3-O-methoxyimino-pregn-4-ene-20-one and its 17α-hydroxy derivative and transcortin from human blood were investigated. The substitution of the progesterone 3-oxo group for a 3-O-methoxyimino group was shown to diminish the affinity of the steroid for transcortin by approximately one order of magnitude irrespective of the substituent’s orientation. The data suggests that progesterone derivatives substituted thereby must have higher bioavailability compared to progesterone and must not significantly affect the biodynamics of glucocorticoid in vivo.
KEY WORDS: selective progesterone analogs, transcortin