Tetillapyrone and Nortetillapyrone, Two Unusual Hydroxypyran-2-ones from the Marine Sponge Tetilla japonica

Abstract

Extraction of the marine sponge Tetilla japonica from the Bay of Thailand furnished tetillapyrone and nortetillapyrone, two unusual tetrahydrofurylhydroxypyran-2-ones, whose structures were established by NMR spectrometry and an X-ray analysis of tetillapyrone.

New ceramides from the sponge Cinachyra cavernosa

“…It was crystallized from acetone as colorless needles with mp 192 -1938C and ½a 27 D þ 27.0 (c 0.1, acetone); NMR and MS spectral data of compound 3 were found completely identical to the data reported in the literature [3].…”

“…Both the extracts were combined after concentration and subjected to solvent partition to afford hexane, chloroform, and n-butanol-soluble and -insoluble fractions. The n-butanol-soluble fraction was chromatographed over silica gel column to give a mixture of two new ceramides 1, 2 and a pyrone previously reported [3] from the sponge Tetilla. The mixture of ceramides was rechromatographed over silica gel (100-200 mesh) to give pure compounds 1 and 2 as white amorphous powders.…”

Antifungal Activity Evaluation of the Constituents of Haliclona baeri and Haliclona cymaeformis, Collected from the Gulf of Thailand

“…All of these evidences, combined with the new isolation of more quantities of tetillapyrone and nortetillapyrone from the marine sponges H. cymaemormis and H. baeri, have led us to re-examine their structures by careful analysis of the HMBC spectra of both compounds. The structure of tetillapyrone (5), previously proposed by us [11], was based on the fact that one carbon signal was missing in the 13 C NMR spectrum and thus the carbon signal at δ109.45 was attributed to C-3 and C-5 of the pyrone ring. As the protons of the methyl group (δ1.76s) on C-3 of the pyrone ring and the hydroxyl proton at δ11.28s, showed crosspeaks with the carbon at δ109.45, we have concluded that the hydroxyl group was on C-6.…”

“…We have previously reported isolation of tetillapyrone (5) and nortetillapyrone (8) from the marine sponge Tetilla japonica, collected from the Gulf of Thailand [11]. Though the structures of both compounds were established by 1 H, 13 CNMR, COSY, NOESY, HETCOR, HMBC and HRMS as well as by X-ray analysis in the case of tetillapyrone (5), there were still some uncertainties with respect to the pyrone moiety.…”

α‐Pyrones and Pyranes from the Plant Pathogenic Fungus Pestalotiopsis scirpina

“…The α-pyrones, such as pestalopyrone, [8] the verrucosapyrones, [12] LL-P880α, [15] and LL-P880β, [24] usually possess C-6 attached side-chains of three to five carbon atoms in length. Scirpyrone A (1) is structurally related to cladobotrin I (11) [25] and tetillapyrone (12), [26] a relatively rare class of α-pyrones with the furylpyranone skeleton, but dif-fers significantly in having a γ-lactone ring joined to the pyrone moiety through C-6 and C-7, rather than a C-5-C-7 connected furan or tetrahydrofuran in known compounds, representing the first described 6-(5-oxotetrahydrofuran-2yl)-2H-pyran-2-one. Scirpyrone B (2), however, differs from the known α-pyrones in possessing a butyl group attached to C-7, and is presumably the ring-opened product of 1.…”