Obscuraminols, new unsaturated amino alcohols from the tunicate Pseudodistoma obscurum: structure and absolute configuration

Crucigasterins A–E, antimicrobial amino alcohols from the Mediterranean colonial ascidian Pseudodistoma crucigaster

“…The relative configuration of the chiral centres C-2 and C-3 was deduced by analysing a series of NOE difference experiments recorded on the corresponding oxazolidinone derivative 8, which was obtained by the reaction of 2 with 1,1 0 -carbonyldiimidazole, according to the procedure applied for related molecules. 5,6 The NOE effects observed between H-3 and H 3 -1 and between H-2 and H 2 -4 suggested that the substituents at both C-2 and C-3 were on the opposite face of oxazolidinone ring. Consequently, H-2 and H-3 were suggested to be in a threo relationship in the acyclic starting compound 2.…”

“…A previous chemical investigation on the same Mediterranean species 4 resulted in the finding of linear erythro 2-amino-alken-3-ols, crucigasterins (i.e., crucigasterin 277, 1). Related linear 2-amino-3-ol alkyl compounds have been encountered in Pseudodistoma obscurum, 6 in Pseudodistoma sp., 5 and also in ascidians of genus Clavelina, 18,19a,b in sponges 20a,b,21 and in the mollusc Mactromeris polynyma. 22 These molecules are closely related to sphingolipids and show interesting bioactivities as antibiotics, 4,5,14,21 antimycotics 4,18,20a,b,21 and as antitumour agents.…”

General synthetic strategy for clavaminols A, C and H

“…These molecules are mostly long chain amino alcohols and their potent biological activity which ranges from antimicrobial activity to inhibition of cell proliferation through prevention of the formation of actin stress fibers in cultured cells, [21][22][23][24][25][26][27][28][29] attracted many natural products chemists.…”

Enantioselective total synthesis of (R)-(−)-complanine

“…Complanine is structurally related to the obscuraminols, isolated from another marine source, the ascidian Pseudodistoma obscurum [2]. Unlike complanine, however, these substances are simple amino alcohols that do not possess any other chemical functionalities.…”