New Derivatives of Natural Acyclic Guanidine Alkaloids with TRPV Receptor-Regulating Properties.

The guanidine alkaloids, dihydropulchranin A (2), prepared from pulchranin A from the sponge Monanchora pulchra and hexadecylguanidine (3), a synthetic analog of pulchranins, were studied for their TRPV channel-regulating activities. Compound 2 was active as an inhibitor of rTRPV1 and hTRPV3 receptors with EC50 values of 24.3 and 59.1 mu M, respectively. Hexadecylguanidine (3) was not active against these receptors.