Synthesis of Physiologically Active Substances from Several Cyclic Monoterpenyl Ketones

Synthesis of ketals of (+) -menthone (1), (+) -carvone (2), (-) -verbenone (3), (+) -camphor (4) and karahanaenone (5) by condensation reaction with ethylene glycol, 1, 2-ethanedithiol and 1, 3-propane dithiol in the presence of foreign synthetic zeolites or p-toluene sulfonic acid was developed. Ketal compounds (6) (18) were obtained and examined for oder and antimicrobial and insecticidal acitivity. (2 R, 5 S) -2-Isopropyl-5-methyl cyclohexanone propylene thioketal (8), 2-isopropyl-5-methyl phenoxy ethanethiol sulfide (13) and (1 R) -1, 7, 7-trimethyl bicyclo [2. 2. 1] heptane-2-on-propylene thioketal (16) emitted odors showing them useful as flavor ingredients. Compound (1 R) -1, 7, 7-trimethyl bicyclo [2. 2. 1] heptane-2-on-ethylene thioketal (15) (at 500 ppm) derived from (4) completely inhibited the growth of propionibacterium acnes. Ketal compound (15) and (16) dervied from (4) showed efficient insecticidal activity of 83100% at 0.51.0 g/m2 toward Tyrophagus putrescentiae (T. putrescentiae) and Dermatophagoides farinae (D. farinae) and toward T. putrescentiae, their activity exceeded that of N, N-diethyl-m-toluamide (DEET).