Synthesis, antimicrobial and antineoplastic activities for agelasine and agelasimine analogs with a beta-cyclocitral derived substituent

Agelasines and agelasimines are antimicrobial and cytotoxic purine derivatives isolated from marine sponges (Agelas sp.). We have synthesized structurally simplified analogs of these natural products starting from beta-cyclocitral. The novel compounds were found to be strong inhibitors of a wide variety of pathogenic microorganisms (incl. Mycobacterium tuberculosis) as well as cancer cell lines. The biological activities were generally in the same range as those previously found for the structurally more complex agelasines and agelasimines isolated in small amounts from natural sources. We also report for the first time that agelasine and agelasimine analogs inhibit growth of protozoa (Acanthamoeba castellanii and Acanthamoeba polyphaga). Acanthamoeba keratitis is an increasingly common and severe corneal infection, closely associated with contact lens wear.     

Antimicrobial and antineoplastic activities of agelasine analogs modified in the purine 2-position

Agelasines are 7,9-dialkylpurinium salts found in marine sponges (Agelas sp.), which display a variety of antimicrobial and cytotoxic effects. We have synthesized simplified agelasine analogs modified in the purine 2-position and examined their antimicrobial and anticancer activities. The compounds were screened against Staphylococcus aureus, Escherichia coli, Mycobacterium tuberculosis, Candida krusei, and Candida albicans, protozoa causing tropical diseases (Plasmodium falciparum, Leishmania infantum, Trypanosoma cruzi, and Trypanosoma brucei), a panel of human cancer cell lines (U-937 GTB, RPMI 8226/s, CEM/s, and ACHN) as well as VERO and/or MRC-5 cells. The results indicate that the introduction of a methyl group in the purine 2-position is beneficial for antimycobacterial and antiprotozoal activity, and that amino groups may enhance activity against several cancer cell lines.