Abstract: Compounds of the formulaRG--A--INwherein IN is a photoinitiator basic structure A is a spacer group and RG is a functional reactive group can be employed as coreactive photoinitiators for photo-polymerization of systems containing ethylenically unsaturated compounds.

Abstract: Compounds of the formulaRG--A--INwhereinIN is a photoinitiator basic structureA is a spacer group andRG is a functional reactive group can be employed as coreactive photoinitiators for photopolymerization of systems containing ethylenically unsaturated compounds.

Abstract: Compounds of the formulaRG--A--INwhereinIN is a photoinitiator basic structureA is a spacer group andRG is a functional reactive groupcan be employed as coreactive photoinitiators for photopolymerization of systems containing ethylenically unsaturated compounds.

Abstract: Compounds of the general formula I ##STR1## wherein Z is CR.sup.1 R.sup.2 (OR.sup.3) or phenyl,R.sup.1 being H, C.sub.1-6 -alkyl or phenyl,R.sup.2 being H, C.sub.1-6 -alkyl or C.sub.1-6 -alkoxy andR.sup.3 being H, C.sub.1-6 -alkyl or C.sub.1-6 -alkanoyl andZ' is Y-[(CH.sub.2).sub.m -X].sub.n -,X being CH.sub.2 or 0,Y being OH; COOH or SO.sub.3 H including the alkali metal, alkaline earth metal or ammonium salts thereof and also the salts thereof with organic nitrogen bases; or NRR' in which R and R' are in each case H, C.sub.1-20 -alkyl or C.sub.1-4 -hydroxyalkyl, if appropriate quaternized or in the form of the acid addition salts, andn and m each being the numbers 1-4, are excellently suitable as photoinitiators for the photopolymerization of ethylenically unsaturated compounds, in particular in aqueous systems.

Abstract: Compounds of the general formula I ##STR1## wherein Z is CR.sup.1 R.sup.2 (OR.sup.3) or phenyl,R.sup.1 being H, C.sub.1-6 -alkyl or phenyl,R.sup.2 being H, C.sub.1-6 -alkyl or C.sub.1-6 -alkoxy andR.sup.3 being H, C.sub.1-6 -alkyl or C.sub.1-6 -alkanoyl andZ' is Y--[(CH.sub.2).sub.m --X].sub.n --,X being CH.sub.2 or 0,Y being OH; COOH or SO.sub.3 H including the alkali metal, alkaline earth metal or ammonium salts thereof and also the salts thereof with organic nitrogen bases; or NRR' in which R and R' are in each case H, C.sub.1-20 -alkyl or C.sub.1-4 -hydroxyalkyl, if appropriate quaternized or in the form of the acid addition salts, andn and m each being the numbers 1-4,are excellently suitable as photoinitiators for the photopolymerization of ethylenically unsaturated compounds, in particular in aqueous systems.

Abstract: The stereospecific preparation of D(+)-biotin is improved by a synthetic route involving the conversion of 3,4-isopropylidene-D-arabinose in which the OH group in the 2-position is not protected, into an ester of 6,9-dihydroxy-7,8-isopropylidenedioxynona-2,4-dienoic acid, the latter then being catalytically hydrogenated and subsequently converted into D(+)-biotin in a manner known per se.

Abstract: Compounds of the formula ##STR1## wherein R.sub.1 is hydrogen, chlorine, phenyl, dialkylamino of 2-4 carbon atoms or alkyl or alkoxy each of up to 18 carbon atoms; R.sub.2 is hydrogen, chlorine, bromine or alkyl or alkoxy each of up to 4 carbon atoms; R.sub.3 and R.sub.4, which can be the same or different, each is hydrogen or alkyl of up to 6 carbon atoms; R.sub.5 is hydrogen or alkyl or alkanoyl each of up to 4 carbon atoms; and R.sub.6 is hydrogen or methyl, with the proviso that not all of R.sub.1 to R.sub.6 simultaneously are hydrogen, are effective photosensitizers, especially for photopolymerization of unsaturated compounds and for hardening of printing dyes.

Abstract: Benzoin oximes of the formula ##STR1## wherein R.sup.1 is alkyl of 3 to 16 carbon atoms, alkenyl of 3 or 4 carbon atoms, 3,7-dimethyl-2,6-octadienyl-1, or -A-S-R.sup.4 ; R.sup.2 and R.sup.3 independently are H, methyl or chlorine; R.sup.4 is alkyl or 1 to 8 carbon atoms; and A is alkylene of 3 or 4 carbon atoms, are chelating agents for copper.