Abstract: The present invention relates to a compound of the formula (I) wherein R1 is an unsubstituted or substituted hydrocarbon radical having a total of 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms, R2 is an unsubstituted or substituted hydrocarbon radical having a total of 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms, or the group NR1R2 is a heterocyclic ring having 3 to 8 ring atoms which is unsubstituted or substituted and contains the nitrogen atom of the group NR1R2 as ring heteroatom and may also contain one or two further ring heteroatoms from the group consisting of N, O and S, and Q is H or a cation. The compounds of the present invention can advantageously be used for the preparation of sulfonylureas and their precursors such as sulfochlorides or sulfonamides.

Abstract: The invention describes the synthesis and use of photoactivated (or caged) fluorescent dyes. Upon illumination at less than about 400 nm the caged dyes release highly fluorescent, water soluble hydroxypyrenesulfonic acid dyes according to the following equation: ##STR1## X, Y, and Z are independently sulfonic acid, a sulfonic acid salt, a hydroxyl group, or hydrogen, with at least one of X, Y, and Z being a sulfonic acid or sulfonic acid salt. LINK is either an ether linkage or a carbonate linkage. BLOCK is a caging group whose photolysis results in liberation of a free hydroxypyrenesulfonic acid dye.The caged fluorescent dyes are useful for application in aqueous solutions, including fluids of biological origin. The caged dyes of the present invention are especially useful for flow tagging velocimetry.

Abstract: When 2-naphthylamine-1,5-disulphonic acid is precipitated from the as-sulphonated reaction mixtures by dilution, a purer product is obtained, with a low level of adherent sulphuric acid, if the precipitation by dilution of the reaction mixture is carried out under precisely defined conditions.

Abstract: In the process according to the invention for the preparation of aminoarylsulphonic acids by catalytic hydrogenation of nitroarylsulphonic acids, a substantial increase in the space-time yield in combination with reduced consumption of the catalyst is achieved by dispersing the hydrogen more finely and by limiting according to the invention the concentration of the nitroarylsulphonic acids to be hydrogenated.

Abstract: Aminoaryl-sulphonic acids can be prepared by reaction of arylamines and sulphuric acid at elevated temperature and under pressure, where water formed and, where appropriate, water present as water of dilution, is left in the reaction mixture until the end of the reaction.

Abstract: The invention relates to monoazo dyes of the formula ##STR1## wherein K is the radical of a coupling component of the benzene, naphthalene or heterocyclic series, and R is hydrogen, halogen, carboxy, a C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy, C.sub.2 -C.sub.6 alkanoylamino, C.sub.1 -C.sub.6 alkylsulfonylamino, C.sub.1 -C.sub.6 alkylsulfonyl, phenyl(C.sub.1 -C.sub.4)alkylsulfonyl or naphthyl(C.sub.1 -C.sub.4)alkylsulfonyl or benzoyl radical, which radicals may be further substituted, or is a ##STR2## group, wherein each of R.sub.1 and R.sub.2 independently of the other is hydrogen or a C.sub.1 -C.sub.6 alkyl, C.sub.5 -C.sub.7 cycloalkyl, phenyl or naphthyl radical, which radicals may be further substituted, and wherein X is hydrogen, halogen or a C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy, C.sub.2 -C.sub.6 alkanoylamino or C.sub.1 -C.sub.6 alkylsulfonylamino radical, which radicals may be further substituted.These dyes give dyeings of good light- and wetfastness properties on polyamide material.

Abstract: New process for the preparation of 1-aminonaphthalene-2,4,7-trisulphonic acid and, if appropriate, 1,7-Cleve's acid, in which 1-nitronaphthalene is reacted by the Piria method with bisulphites in a manner which is known per se, the sulphamate mixture obtained in this Piria reaction is sulphonated with sulphur trioxide in sulphuric acid to give 1-aminonaphthalene-2,4,7-trisulphonic acid and, if appropriate, this is hydrolysed to 1,7-Cleve's acid by heating in aqueous sulphuric acid.

Abstract: Compounds of formula ##STR1## wherein X is long-chain alkyloxy, long-chain alkylamino or long-chain dialkylamino,M is alkali metal, pyridinium or ammonium,Y is hydroxy or long-chain alkyloxy,which are especially useful in photometric and fluorimetric investigations of lipids and lipid-water interactions and of cationic biomolecules such as nicotine adenine dinucleotide.