| 摘要 |
<p>Cpds. of formula:- (where X = H, OH or NR2R3; D = O, S or NR4; Q = O or NH; V = alkyl, aryl or aralkyl; R and R1-R4 are H or opt. substd. hydrocarbyl, pref. Me or Et; rings A and B are opt. further substd) colour formers for pressure-sensitive copying and duplication systems. They may be prepd. by reacting the corresp. leuco cpd. with an alkyl-, aralkyl- or aryl-chloroformate or isocyanate.</p> |
