Methyl methane thiosulfinate

S-alkylcysteinase S-methylcysteine S-methylcysteine sulfoxide Methanethiol Methyl methane-thiosulfinate... 

Mixing of 5-ethyl ethanethlosulfinate with 5-methyl methane-thiosulfinate in the dark, either neat or in benzene solution, rapidly establishes an equilibrium with the complete scrambling of the sulfenyl and sulfinyl fragments (eq 6). ... 

Garlic also contains S-propylcysteine-sulfoxide (PCSO) and S-methylcysteine-sulfoxide (MCSO). PCSO can generate over 50 compounds depending on temperature and water content. The action of allinase on the mixture of alliin, PCSO, and MCSO can produce many other molecules, including allyl methane thiosulfinate, methyl methanethiosulfinate, and other mixed or symmetrical thiosulfinates (R-S-S-R ), where R and R are methyl, propyl, and allyl groups. 

When onion is cut or cmshed, ( )-5 -l-propenyl-L-cysteine sulfoxide (isoalliin) is converted into ( )-l-propene-l-sulfenic acid. Different from garlic, (Z)-thiopropanal S-oxide, a lachrymatory factor, is formed from the sulfenic acid by lachrymatory factor synthase (Figure 18.6). The remaining ( )-l-propene-l-sulfenic acid and methyl sulfenic acid produced from 5 -methyl-L-eysteine sulfoxide ean form methyl 1-pro-pene-thiosulfinate and 1-propenyl methane thiosulfinate that are further converted to sulfides such as 1-propenyl methyl disulfide and 1-prope-nyl methyl trisulfide. 

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