Abstract: Compounds of the formulae wherein Z is —OR1, —SR1, —NR1R2, Y is —OR3, —SR3, or —NR3R4, at least one of R1, R2, R3, R4, R5, and R6 is hydrogen, at least one of R1, R2, R3, R4, R5, and R6 is other than hydrogen, at least one Z or Y within the compound is —NR1R2 or —NR3R4, R1, R2, R3, R4, R5, R6, and R7 each, independently of the others, is hydrogen, alkyl, aryl, arylalkyl, or alkylaryl, and wherein R7 can also be alkoxy, aryloxy, arylalkyloxy, alkylaryloxy, polyalkyleneoxy, polyaryleneoxy, polyarylalkyleneoxy, polyalkylaryleneoxy, silyl, siloxane, polysilylene, polysiloxane, or wherein X is a direct bond, oxygen, sulfur, —NR40— wherein R40 is hydrogen, alkyl, aryl, arylalkyl, alkylaryl, or —CR50R60— wherein R50 and R60 each, independently of the other, is hydrogen, alkyl, aryl, arylalkyl, or alkylaryl.