Euthyroideones

Three new alkaloids, euthyroideones A, B and C (11-13) were isolated from the New Zealand bryozoan Euthyroides episcopalis [38]. All three compounds contain the unique heterocyclic pyrido(4,3-h)-l,4-benzothiazine skeleton. The structure of euthyroideone A (11) was determined by X-ray crystallography, NMR spectroscopy and mass spectrometry. Euthyroideone B (12) exhibited modest cytotoxicity against the BSC-1 cell line [38],... 

Most of the reported sulfone-containing marine metabolites have been obtained from sponges and bryozoa. The hypotaurocyamine-containing agelasidines, some adociaquinone derivatives, and the euthyroideones constitute small groups of compounds bearing a sulfone group. 

A sulfone group incorporated within a l,l-dioxo-l,4-thiazine ring is also present in 6-(p-hydroxyphenyl)-2i/-3,4-dihydro-l,l-dioxo-l,4-thiazine (286), a compound obtained from the sponge Anchinoe tenacior [211], and in euthyroideones A-C (287-289), which are brominated quinone methides isolated from the New Zealand bryozoan Euthyroides episcopalis (order Cheilostomatida, suborder Ascophotina, family Euthyroididae) [212]. The spectral data of euthyroideone A (287), secured by X-ray analysis, was used for the structural determination of euthyroideones B (288) and C (289). Compound 288 showed a weak cytotoxic activity towards the BSC-1 cell line. 

Morris BD, Prinsep MR (1998) Euthyroideones, Novel Brominated Quinone Methides from the Bryozoan Euthyroides episcopalis. J Org Chem 63 9545... 

Morris, B.D. and Prinsep, M.R. (1998) Euthyroideones, novel brominated quinone methides from the bryozoan Euthyroides episcopalis. J. Org. Chem., 63,9545-9547. 

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