NOVEL ISOBENZOTHIAZOLON CHROMOGEN THIOL INDICATOR AND DERIVATIVE THEREOF

PURPOSE: To detect thiol group generated by chemical reaction or enzyme reaction by using chromatic primitive thiol indicator of new type containing isobenzothiazole as a base. CONSTITUTION: The novel synthetic chromatic primitive thiol indicator isobenzothiazolone derivative has the structure of a formula I. In the formula I, at least one of R and R is nitro group or arylazo group. If one of the R and R is substituent, one of the R and R may be hydrogen. R substituent is selected from alkyl group or amino group having at least about seven carbon atoms (and functionalized form given by desired solubility and reactivity to the indicator). The compound particularly preferable for useful to detect the thiol in aqueous atmosphere is R substituent having sufficient polarity to give water solubility to the compound such as, for example R is the compound having-(CH2 )n -NR R (where n is 2 to 6, R and R are alkyl group of simple structure or hydrogen).