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Azopyrazole disperse dyes 8–12 could be synthesized either by condensing ethyl 3-hydroxy-2-aryldiazenyl butenoates 3–7 with S-methyl hydrazine carbodithioate 1 or by coupling the parent pyrazole 2 with diazotized aniline, p-substituted anilines and/or 4-aminoantipyrine. These dyes were applied to polyester fabrics using a high-temperature dyeing method at 120 °C and displayed yellow to orange hues. Raman spectra of the dyed samples undoubtedly excluded ring dyeing and were found to agree with the proposed structures. The synthesized disperse dyes were found to possess very good dyeing properties, as indicated by color strength measurements, and all of them except dye 12 had a color strength (K/S) value ranging from 19–23. The dyed fabrics exhibited excellent fastness to washing and dry and wet rubbing as well as light fastness, which varied from moderate to very good. The antimicrobial activities of the synthesized pyrazoles 2 and 8–12 as well as the dyed fabric samples against Escherichia coli and Staphylococcus aureus were measured, and the results showed very good activity.

The reason of color differences caused by different degree of esterification disperse dyes were investigated by disperse orange 30, disperse red 167:1, disperse blue 79:1 with different degree of esterification. The results showed that the changes of light absorbance abilities and melting points caused by ester groups had no obvious correlation with the color differences caused by ester groups. The changes in the solubilities and affinities caused by the ester groups were the fundamental reason for the changes in the dyeing properties of disperse orange 30, disperse red 167:1 and disperse blue 79:1. As a joint result of the decrease in solubilities and affinities, the dye sorption in polyethylene terephthalate of unesterified disperse orange 30, unesterified disperse red 167:1 and unesterified disperse blue 79:1 were reduced by 37.7%, 83.6% and 54.6%, respectively, compared with those of the corresponding completely esterified dyes.

Synthesis of linear and angular furocoumarins with new skeleton structure of potential photobiological feature interest was carried out through Williamson reaction of hydroxycoumarins with 3-chloro-2-butanone followed by cyclization with polyphosphoric acid or by heating in a strongly alkaline solution. The photooxygenation reactions of synthesized furocoumarins were performed in chloroform and in the presence of tetraphenylporphyrin as singlet oxygen sensitizer (1O2). The photooxygenation reactions afforded the photocleaved product through [2 + 2] cycloaddition and the photooxygenated products through ene reaction and [4 + 2] cycloaddition. The photoproducts were isolated and fully characterized by spectral analyses.

Synthesis of 9-methyl-1-phenyl-7H-furo[3,2-f]chromen-7-one and 4,9-dimethyl-3-phenyl-7H-furo[2,3-f]chromen-7-one as angular furocoumarin derivatives were carried out through Williamson reaction of hydroxycoumarins with phenacyl bromide followed by cyclization in polyphosphoric acid. The photooxygenation of synthesized furocoumarins in the presence of tetraphenylporphine as singlet oxygen sensitizer at room temperature gave the photo-cleaved product, o-benzoylhydroxy derivatives, through [2+2] cycloaddition of singlet oxygen with the double bond of the furan moiety. o-Benzoylhydroxy derivatives were prepared through the photooxygenation reactions and Fries rearrangement.