Decandrinin, an unprecedented C₉-spiro-fused 7,8-seco-ent-abietane from the Godavari mangrove Ceriops decandra

Abstract

SummaryDecandrinin (1), an unprecedented C9-spiro-fused 7,8-seco-ent-abietane, was obtained from the bark of an Indian mangrove, Ceriops decandra, collected in the estuary of Godavari, Andhra Pradesh. The constitution and the relative configuration of 1 were determined by HRMS (ESI) and extensive NMR investigations, and the absolute configuration by circular dichroism (CD) and optical-rotatory dispersion (ORD) spectroscopy in combination with quantum-chemical calculations. Decandrinin is the first 7,8-seco-ent-abietane.

Marine natural products

“…In addition to a series of mildly antioxidant glycosides, marinoids F-M 1374-1381, reported from the whole fruits of the mangrove Avicennia marina, 907,908 seco-diterpene 1382 (Ceriops decandra), 909 cinnamides 1383-1387 (Micromelum falcatum, mangrove associate), 910 protolimonoids 1388-1394 (Xylocarpus granatum), 911 and limonoids 1395-1401, 912 1402-1404, 913 1405-1408, 914 1409-1418, 915 1419-1422 916 and 1423 917 (X. rumphii and X. granatum) were also isolated from mangroves or their associates. The absolute conguration of the unusual spiro-secoabietane decandrinin 1382 was secured via analysis of experimental and calculated ECD and ORD chiroptical data 909 while of the limonoids reported, the structures of xylorumphiin G 1398, 912 xylogranatopyridine A 1402, 913 granatumin L 1409 915 and granatumin Y 1422 916 were established by single crystal Xray diffraction studies.…”

Structure elucidation of two new diterpenes from Vietnamese mangrove Ceriops decandra

“…The leaf extract has been reported to exhibite antinociceptive activity [3]. Previous phytochemical investigations on this plant resulted in the isolation of lupane-and ursane-type triterpenoids from the leaf [4], beyerane-, pimarane-, kaurane-, and abietanetype diterpenoids from the roots [1,[5][6][7], and abietaneand podocarpane-type diterpenoids from the barks [2,8]. In an ongoing search for bioactive natural products from mangroves [9,10], we report here the isolation, structure elucidation, and cytotoxicity assay of two new diterpenes, ceridecandrin A (1) and B (2), from C. decandra stem barks.…”

A New Bis-seco-abietane Diterpenoid from Hyptis crenata Pohl ex Benth

“…6 Of the 7,8-seco-abietane-type, however, only two compounds are known: 7,8-seco-paraferruginone from Salvia prionitis 7 and 7,8-seco-7(20),11(20)-diepoxy-7,14-dihydroxyabieta-8,11,13-triene from Hyptis martiusii. 8 In comparison with these compounds, hyptisolide A (1), is unique in that in addition to the C-7/C-8 bond, the C-11/C-12 bond of the abietane skeleton has also been oxidatively cleaved.…”

“…Fraction 4 was separated on a silica gel column by elution with a CHCl 3 /MeOH (100:0, 20:1, and 10:1) solvent system to afford ten subfractions (F. 4 6), an oxymethine carbon (δ C 77.0), two aliphatic quaternary carbons (δ C 31.2, and 50.6), two aliphatic methines (δ C 26.8 and 53.6), three aliphatic methylenes (δ C 19.5, 29.2, and 34.8), four methyl carbons (δ C 20.9 × 2, 28.5, and 28.6), and two methoxy carbons (δ C 53.1 and 53.3).…”