Ga. Rosenthal et al., INSECTICIDAL PROPERTIES OF SOME DERIVATIVES OF L-CANAVANINE, Journal of agricultural and food chemistry, 43(10), 1995, pp. 2728-2734
The canavanine derivatives D-canavanine and L-homocanavanine as well a
s the 1-methyl and 1-ethyl esters of L-canavanine were synthesized and
evaluated for biological activity in fifth instar larvae of the tobac
co hornworm, Manduca sexta [Sphingidae]. While L-homocanavanine did no
t increase intrinsic toxicity, it was as deleterious as L-canavanine.
D-Canavanine was biologically active, as demonstrated by its ability t
o cause larval edema, but the D-enantiomer had little ability to elici
t the larval growth inhibition and pupal deformity which are hallmarks
of canavanine toxicosis and was postulated to be linked to aberrant p
rotein production. The 1-methyl and 1-ethyl esters of L-canavanine wer
e synthesized to determine if enhancing canavanine's hydrophobicity mi
ght increase its bioavailability. Our experiments revealed that these
esters are less toxic than canavanine; the ethyl ester disrupted larva
l growth more than did the methyl analogue.