Reactions of Pyrazinethiones and Pyrazinethiols

The hydrolysis and desulfurization of these thiones and thiols appear to have escaped attention recently. Other reactions are illustrated in the following examples  

2-Mercaptomethylpyrazine (18) gave bis(pyrazin-2-ylmethyl) disulfide (19) (I2, CHC13, warm, briefly %) 674 also other such oxidations.1211 

2(l//)-Pyrazinethione (20) gave A0V-diethyl-2-pyrazinesulfonamide (21) (KHF2, Et2NH, MeOH, Cl2j, 10°C, 45 min 68%) 1602 also analogous examples.1381 

3-Amino-6-bromo-2(l//)-pyrazinethione (22) gave 5-bromo-3-methylthio-2-pyrazinamine (23) (1 M NaOH, Mel, 20°C, 20 min 80%).1012 2(l//)-Pyrazincthione gave 2-(but-3-ynylthio)pyrazine (24) (ICII2CH2C CH, EtjN, H20,70°C, 3 h 44%).361 

6-Diisopropyl-2(l//)-pyrazinethione gave 2-ethoxycarbonylmethylthio-3,6-diisopropylpyrazine (25) (Et02CCH2Cl, Na2C03, AcMe, 20°C, 15 h  

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