The Biotransformation Of Exemestane By Colletotrichum Lini Cgmcc 34486 And Structure-activity Assay Of Its Analogues

Our previous studies have indicated that Colletotrichum lini CGMCC 34486 can be capable of 3-ketosteroids.In order to verify transformation rules of 3-ketosteroids by C.lini CGMCC 34486,the biotransformation of exemestane by C.lini CGMCC 34486 was studied.The structures of the transformation products were identified by X-ray analysis.Besides the biological activity of exemestane and its analogues was also studied.Summarize structure-activity relationship on the immunoregulatory activity to provide the oretical guidance for the increasing activity of steroids.The biotransformation of exemestane by C.lini CGMCC 34486 was studied.C.lini CGMCC 34486 can be capable of hydroxylation exemestane at C-11? and C-15a.The structures of three compounds were identified by X-ray as 11?-hydroxy-6-methylen androsta-1,4-diene-3,17-dione,11?,15?-dihydroxy-6-methylenandrosta-1,4-diene-3,17-dione and 11?,17?-dihydroxy-6-methylenandrosta-1,4-dien-3-one.The last two as a novel compound was reported for the first time.To test whether the same hydroxylase or different hydroxylases is capable of 11?-and 15a-hydroxylation,transformation experiments with cycloheximide were carried out.Results showed that different enzymes are accounted for hydroxylations in positions 11? and 15?.Furthermore,the structure-activity relationship on the immunoregulatory activity were also studied.Influence of the structures of compounds on the activity was conclued.It found that,C-6 methylene influenced the activity most.The more higher polar,the more greater activity.11 a,15a-hydroxy derivatives of these compounds are more active than low polar substrates.The presence of additional 1(2)-double bonds in molecule can also improve the activity.And in the activation of NK and NKT cells,nonthing was found about correlation between structure and activity...