| 摘要 |
The present invention provides compounds having the formula: <CHEM> in which R is hydrogen or C1-C4alkyl, preferably hydrogen and Y is hydrogen, C1-C4alkyl, C1-C4alkoxy, CF3, halogen (F, Cl, Br or I) or SO3M in which M is H, Na, K, Ca, Mg, ammonium, mono-, di-, tri- or tetra-C1-C4alkylammonium, mono-, di- or tri-hydroxyalkylammonium or ammonium that is di- or tri-substituted with a mixture of C1-C4alkyl and C1-C4hydroxyalkyl groups; a process for their production by partial dehydration of compounds having the formula: <CHEM> ; and their use as intermediates in the production of asymmetric or symmetric fluorescent whitening agents. |
