New Tricyclic Diterpenes from the Sponge Higginsia sp

Abstract

The structure of a new tricyclic diterpene (1) isolated from an unclassified Higginsia sp. has been determined by X-ray crystallographic methods. The structures of two related co-metabolites have been deduced from a comparison of their spectroscopic properties with those of (1).

Polyoxygenated Diterpenes from the Sponge Phorbas sp.

“…A methyl singlet at δ Η 1. [13][14][15][16][17][18][19][20] exhibited long-range correlations with carbon signals at δ C 78.9 (CH-11), 74.1 (CH-9), 53.4 , and 47.6 (C-10), implying that the former three methine carbon atoms were connected to the latter quaternary carbon. The combination of the 1 H spin systems observed by an analysis of the COSY spectrum with the aforementioned HMBC correlations allowed the construction of an isopropyl-substituted five-membered ring.…”

“…6 CH 5.81,d (10.7) C-6, C-9, C-10, C- 19 9 125.1 CH 6.22, dd (15.0, 10.7) C-7, C-8, C- 11 10 139. 2 CH 5.49,dd (15.0,7.9) C-8, C-11, C- 18 11 36.9 CH 2.18, dq (7.9,6.7) C-9, C-10, C-12, C-13, C- 18 12 37.4 CH 2 1.34, m C-10, C-11, C-13, C-14, C- 18 13 26.1 CH 2 1.96, dt (7.1, 7.4) C-11, C-12, C-14, C- 15 14 124.9 CH 5.10, t (7.1) C-12, C-13, C-16, C- 17 15 131.5 C 16 26.0 CH 3 1.69, s C-14, C-15, C-17 17 17.9 CH 3 1.60, s C-14, C-15, C- 16 18 20.9 CH 3 1.01, d (6.7) C-10, C-11, C-12 19 15.2 CH 3 1.72, br s C-6, C-7, C- 8 20 181.8 C…”

Marine natural products

“…Three metabolites of Spongia oficin- 186), (187), and (188)J; these have a carbon skeleton that had not previously been reported from marine sources. 184 The structure of the dihydroxy-ketone (186) was determined by X-ray analysis. The nor-diterpene ( 189) is a cyclic peroxide from a species of Latruncufia that had been collected off New South Wales,…”

“…afis,180 i.e. (14R)-15-acetoxyisoagath-12-en-16-a1(180) and the (14R)-and ( 14S)-isomers of isoagath-12-ene-15,16-dial [( 18 1) and (182)], have been synthesized from a labdane precursor.181 Two new di terpene derivatives of hypotaurocyamine, namely agelasidine B(183) and agelasidine C(184), were isolated from Agefas nakamurai. '82 The structures of agelasidines B(183) and C ( I 84) were determined by interpretation of spectral data and their absolute configurations were shown to be opposite to that of ageline A ( l85).Ig3 The agelasidines are antimicrobial, inhibit the enzymic activity of Na+/K+-transporting ATPase, and inhibit the contraction of smooth muscle.A species of Higginsia from Australia has yielded three new tricyclic diterpenes [(…”

7-6-5 Tricarbocyclic Diterpenes

“…Cyrneines are cyathanes isolated from the mushroom Sarcodon cyrneus. Nigernins, Onychiols, and Other Derivatives [104][105][106][107][108][109][110][111] Nigernins A-F 171-176 are cyathanes isolated from the fruiting bodies of basideomycete Phellodon niger. 5.9; Table 5.8).…”