Reagents methyl / -nitrobenzene sulfonate

Methyl p-Nitrobenzenesulfonate, p-Nitrobenzene-sulfonic acid methyl ester. C,HTNO,S mol wt 217.20. C 38.71%, H 3.25%, N 6.45%, O 36.83%, S 14.76%. Reagent for selective methylation or cysteine residues in chemical modification of proteins Nakagawa, Bender, J. dm. Chem. Sac, 91, 1566(1969). Procedure Heinrikson. Biochem. Bio-phys. Res. Common. 41, 967 (1970). Prepd by the general method of reacting p-nitrobenzenesulfony] chloride with alcohols. See Morgan, Cretcher, J. Am. Chem Soc. 70, 375 (1948). 

Although the uses of dimethyl sulfate and methyl toluene-p-sulfonate are well known, in many cases these reagents have been used in solution, e.g. in nitrobenzene, in addition to the older... 

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