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A hexacyclic ent-trachylobane diterpenoid possessing an oxetane ring from Mitrephora glabra.

ABSTRACT: [chemical reaction: see text]. Three new ent-trachylobane diterpenoids (1-3) were isolated and structures elucidated from Mitrephora glabra Scheff. (Annonaceae). Mitrephorone A (1) possesses a hexacyclic ring system with adjacent ketone moieties and an oxetane ring, both of which are unprecedented among trachylobanes. All compounds were evaluated for cytotoxicity against a panel of cancer cells, where 1 displayed the most potent and broadest activity, and against a battery of antimicrobial assays, where all compounds were approximately equipotent.

SUBMITTER: Li C

PROVIDER: S-EPMC2442714 | biostudies-literature | 2005 Dec

REPOSITORIES: biostudies-literature

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A hexacyclic ent-trachylobane diterpenoid possessing an oxetane ring from Mitrephora glabra.

Li Chen C Lee Dongho D Graf Tyler N TN Phifer Sharnelle S SS Nakanishi Yuka Y Burgess Jason P JP Riswan Soedarsono S Setyowati Fransisca M FM Saribi Achmad M AM Soejarto Djaja D DD Farnsworth Norman R NR Falkinham Joseph O JO Kroll David J DJ Kinghorn A Douglas AD Wani Mansukh C MC Oberlies Nicholas H NH

Organic letters 20051201 25

[chemical reaction: see text]. Three new ent-trachylobane diterpenoids (1-3) were isolated and structures elucidated from Mitrephora glabra Scheff. (Annonaceae). Mitrephorone A (1) possesses a hexacyclic ring system with adjacent ketone moieties and an oxetane ring, both of which are unprecedented among trachylobanes. All compounds were evaluated for cytotoxicity against a panel of cancer cells, where 1 displayed the most potent and broadest activity, and against a battery of antimicrobial assay ...[more]

PMID: 16321028

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