Steroid epoxide cleavage by Cylindrocarpon radicicola☆

Flexibility of the endogenous progesterone lactonisation pathway in Aspergillus tamarii KITA: transformation of a series of cortical steroid analogues

“…Of those, which have reported in yeast [19] and fungi [7,20], they have resulted in retention of alpha stereochemical configuration. For example 16␣,17␣-epoxyprogesterone was incubated with the fungus Cylindrocarpon radicicola [7] resulting in 16␣-hydoxy-17␣-oxa-d-homo-androst-1,4-dien-17-one.…”

“…For example 16␣,17␣-epoxyprogesterone was incubated with the fungus Cylindrocarpon radicicola [7] resulting in 16␣-hydoxy-17␣-oxa-d-homo-androst-1,4-dien-17-one. Although epoxide opening with inversion of stereochemistry can occur, for example by an activated oxygen species such as a per acid, it is unlikely that this is occurring in our transformation as it would result in a diol being formed [18,21] on ring D. A more likely scenario can be centred around the mechanism where the epoxide opens to form a 16␣-hydroxy metabolite reported with the fungus C. radicicola [7] (Fig. 2).…”

“…A variety of fungi [1][2][3][4][5][6][7] have been identified which can stereospecifically degrade the 17␤-acetyl side chain of progesterone in high yield to give the ring D steroidal lactone testololactone (5). Of these fungi Aspergillus tamarii KITA is the most efficient, with yields from transformation reported at 70% [1].…”

Monooxygenase-Mediated Baeyer−Villiger Oxidations

“…[33] Initial structure acceptance studies revealed significantly different substrate profiles for steroid monooxygenases. [34] A BVMO from C. radicicola was purified by affinity chromatography and oxidatively cleaved the side chains of several steroidal structures. [35,36] However, a similar enzyme [37] originating from Rhodococcus rhodochrous displayed very high selectivity for progesterone and 11-hydroxyprogesterone.…”

Reduction of the 20-Carbonyl Group of C-21 Steroids by Spores of Fusarium solani and Other Microorganisms. I. Side-Chain Degradation, Epoxide Cleavage, and Substrate Specificity

“…Conversion of 16a,17a-oxidoprogesterone into 16a-hydroxy-1-dehydrotestosterone and 16a-hydroxy-1-dehydrotestololactone. Conversion, probably via side-chain cleavage followed by epoxide opening, demonstrated by El-Tayeb et al (6) in C. radicicola.'…”