306 
PACIFIC SCIENCE, Vol. XXII, July 1968 
(a) 
1648 cm 
OCH 
H 
H 3 C H 
1622 cm 
-1 
dihydro -MIL 
R 
1560 -1575 cm' 1 
RCH-CHR (trans) 
hch) 
955-966 cm' 1 
(7)-CH=CH- 
4- 
+ 
styryl- 
Och 2 -ch 2 - 
+ 
— 
phenylethyl- 
styryl- 
— 
+ 
pheny lethy l 
— 
— 
UV spectra (Hansel et aL, 1967) : Again 
it is best to begin with the basic lactone chrorno- 
phore, the dihydromethyltriacetoacid lactone 
(DH-MTL). We are dealing here with an 
s-Zra/zr-fixed enone system, comparable to that 
of parasorbic acid (PSS). DH-MTL differs 
from PSS in the position of the maximum by 
an increment of 30mp, an effect which can be 
ascribed to the p-methoxy substituent (Fig. 14). 
The magnitude of the increment is in good 
