. ", with the proviso that when n is 0 or 1, then at least one of R4a or R8 is other than H or methyl; Y selected from:hydroxy, C1 to C10 alkyloxy, C3 to C11 cycloalkyloxy, C6 to C10 aryloxy, C7 to C11 aralkyloxy, C3 to C10 alkylcarbonyloxyalkyloxy, C3 to C10 alkoxycarbonyloxyalkyloxy, C2 to C10 alkoxycarbonylalkyloxy, C5 to C10 cycloalkylcarbonyloxyalkyloxy, C5 to C10 cycloalkoxycarbonyloxyalkyloxy," . . .