Synthesis, structural assignments and antiinfective activities of 3--benzyl-carvotacetone and 3-hydroxy-2-isopropyl-5-methyl--benzoquinone.

In an attempt to synthesize carvotacetone analogues, new 3--benzyl-carvotacetone ( and previously reported 3-hydroxy-2-isopropyl-5-methyl--benzoquinone () were synthesized from piperitone (). In this work, we describe the synthesis of and other analogues from . Luche reduction of to -piperitol (, followed by benzylation yielded 3--benzyl-piperitol (). Riley oxidation of afforded corresponding ketone , and 3-benzyloxy-4-isopropylcyclohex-1-enecarbaldehyde (. Structures of these compounds were determined based on NMR, IR and LC-MS spectral data. Compound , exhibited antiplasmodial activities against chloroquine-sensitive (D6) and resistant (W2) strains of with IC value of 0.697 and 0.653µg/mL, respectively. In addition, compound was active against with an IC value of 3.11µg/mL, compared to reference standard fluconazole (IC value of 1.87µg/mL), while and were inactive against both organisms. This is the first report of the antiplasmodial and anticryptococcal activity of compound .