Folpet [N-(Trichloromethylthio) phthalimide ] 
C!4_ and $35- labeled folpet was used to study the fate of folpet in 
cultures of Saccharomyces pastorianus, Folpet was rapidly degraded and 
most of the C*'-label could be recovered as phthalimide. S3°_label was 
distributed through the gas phase, culture medium and cells, in both 802 
ethanol-soluble and -insoluble fractions (1670). 
In studies of the reactions of folpet with proteins, nucleic acids 
and subscellular components of Saccharomyces pastorianus, sulfur equivalent 
to 32, 17, 16 and 5 micrograms of folpet was bound per milligram of protein 
by components of a dialyzed S. pastorianus extract, alcohol dehydrogenase, 
glyceraldehyde-3-phosphate dehydrogenase and lysozyme, respectively. Very 
little $3° was bound by bovine DNA, yeast RNA or wall fragments of S. 
pastorianus. Reaction of folpet with cell components could proceed by one 
of the two paths shown (1671). 
Other studies have shown that folpet reacts with thiols such as 
cysteine and glutathione. The reaction does not occur below pH 4.0 or 
5.0, respectively, and the rate rises rapidly above pH 6.0 (889). 
C 
R = is Cr 
A C 
' ' ft 
R = N-S-C-Cl , +2-°RSH > HS-C-Cl, + R=NH + RSSR 
il 
0 
il} 
0 
+ ; 
H»0 RNH 9 —— 
2 HCl + O=C=S “&—Cl,—C=S — 3» RNH-C-NHR 
S 
Ag ft 
Rs-fesr’ + 2HC1 reer 
B 
1 
RNH> RNH-S-C-C13 
¢ 
R = N-S-C-Cl, + RSH > R=NH + RS-s-C-Cl., 
ROH RO-S-C-C1, 
213 
