| 摘要 |
Novel benzofuranyl benzimidazoles of the formula <IMAGE> wherein R1 represents a hydrogen atom, an alkenyloxy or cycloalkyloxy radical, an unsubstituted or substituted alkoxy, phenylalkoxy or phenoxy radical, each of R2 and R3 independently represents a hydrogen atom, an alkyl or alkoxy radical, a halogen atom, or, if R1 represents hydrogen, together in the ortho-position to each other they represent a radical of the formula -CH=CH-CH=CH-, -O-CH2-O- or -O-CH2-CH2-O-, R4 represents a hydrogen atom, an alkyl, alkoxy or phenyl radical, R5 represents a sulpho or carboxyl group or the functional derivatives thereof including the cyano group or the trifluoromethyl group, R6 represents a hydrogen or halogen atom, an alkyl or alkoxy radical, R7 represents a cycloalkyl, alkenyl, or unsubstituted or substituted alkyl, phenyl or phenylalkyl radical, or, if n is 0, also represents a hydrogen atom, R8 represents a hydrogen atom, a cycloalkyl, alkenyl, or unsubstituted or substituted alkyl or phenylalkyl radical, Aw(-) represents a colorless anion of an inorganic or organic acid and w represents the valency of the anion A, and n is 0 or 1, their preparation as well as their use as optical brighteners are disclosed. |
