(3 hydroxypropyl)ester 1,8 diazabicyclo[5.4.0]undec 7 ene 3 (3,4 dicyano phenoxy) propyl ester 4 nitrophthalonitrile Spectroscopy Synthesis Thiol-phthalocyanines absorption spectrophotometry alkene derivative article butanol chemical structure controlled study macrocyclic compound methoxide sodium nitrile phthalocyanine phthalocyanine zinc phthalonitrile sodium derivative spectrofluorometry substitution reaction sulfur synthesis thioacetic acid thiol derivative unclassified drug zinc acetate