Styelid ascidians

McDonald LA, Swersey JC, Ireland CM, Carroll AR, Coll JC, Bowden BF, Fairchild CR, Cornell L (1995) Botryllamides A-D, Two Brominated Tyrosine Derivatives from Styelid Ascidians of the Genus Botryllus. Tetrahedron 51 5237... 

Similar metabolites which appear to be derived from tyrosine and brominated tyrosine include botryllamides A-D (31-34), which were isolated from brightly coloured styelid ascidians from the genus Botryllus collected in Fiji and in Australia [32]. Botryllamide D was reported to exhibit marginal cytotoxicity after 72 hour exposure to the human colon cancer cell line HCT 116 (IC50 17 pg/mL), but were inactive in vivo. The rubrolides, which were isolated from Riterella rubra [33] may well be derived from precursors similar to the botryllamides, however, the rubrolides are not alkaloids so have been mentioned here only for comparative purposes. 

Hirose E. and Mukai H. 1992. An ultrastructural study on the origin of glomerulocytes, a type of blood cell in a styelid ascidian, Polyandrocarpa misakiensis. J Morphol 211 269-273. 

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