Bayer Aktiengesellschaft

Carl Wolfgang Schellhammer

Florin Seng

4-Sulphonamidosalicylaldehydes of the formula ##STR1## wherein R represents an optionally substituted straight-chain or branched alkyl or cycloalkyl group or an optionally substituted aryl group, are valuable intermediates for the preparation of optical brighteners.

Sulphonamidosalicylaldehydes

Coumarins of the formula ##STR1## wherein R denotes an alkyl radical with 1 to 4 C atoms, which is optionally substituted by halogen atoms or a phenyl radical which is optionally substituted by halogen, C.sub.1 -C.sub.4 -alkyl or C.sub.1 -C.sub.4 -alkoxy and

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Schildgen, Germany

Carl Wolfgang Schellhammer