Synthesis, antimicrobial evaluation, and structure-activity relationship of α-pinene derivatives.
Several (+)- and (-)-α-pinene derivatives were synthesized and evaluated for their antimicrobial activity toward Gram-positive bacteria Micrococcus luteus and Staphylococcus aureus, Gram-negative bacterium Escherichia coli, and the unicellular fungus Candida albicans using bioautographic assays. (+)-α-Pinene 1a showed modest activity against the test organisms, whereas (-)-α-pinene 1b showed no activity at the tested concentration. Of all the α-pinene derivatives evaluated, the β-lactam derivatives (10a and 10b) were the most antimicrobial. The increase in the antimicrobial activity of 10a compared to 1a ranged from nearly 3.5-fold (C. albicans) to 43-fold (S. aureus). The mean ± standard deviation for the zone of inhibition (mm) for 10a (C. albicans) was 31.9 ± 4.3 and that for S. aureus was 51.1 ± 2.9. Although (-)-α-pinene 1b was not active toward the test microorganisms, the corresponding β-lactam 10b, amino ester 13b, and amino alcohol 14b showed antimicrobial activity toward the test microorganisms. The increase in the antimicrobial activity of 10b compared to 1b ranged from 32-fold (S. aureus) to 73-fold (M. luteus). The mean ± standard deviation for the zone of inhibition (mm) for 10b (S. aureus) was 32.0 ± 0.60 and that for M. luteus was 73.2 ± 0.30.
Department of Chemistry and ‡Department of Biology, State University of New York , 1 Hawk Drive, New Paltz 12561, United States.
Preeti
P
Dhar
PuiYee
P
Chan
Daniel T
DT
Cohen
Fadi
F
Khawam
Sarah
S
Gibbons
Teresa
T
Snyder-Leiby
Ellen
E
Dickstein
Prashant Kumar
PK
Rai
Geeta
G
Watal
D000890:Anti-Infective Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D000081008:Bicyclic Monoterpenes; D002176:Candida albicans / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D039821:Monoterpenes / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D013329:Structure-Activity Relationship
D000890:Anti-Infective Agents; D000081008:Bicyclic Monoterpenes; D039821:Monoterpenes; C005451:alpha-pinene