Mechanism of skin photosensitization by forucoumarins

Psoralens as Photoactive Probes of Nucleic Acid Structure and Function: Organic Chemistry, Photochemistry, and Biochemistry

“…Both tritium and carbon-14 labeled psoralens have been synthesized by routine synthetic manipulation to obtain radiolabeled derivatives. Methods used include exchange reactions with tritium gas (88,89) and tdtiated water (25), catalytic reduction (80,81) and hydrogenolysis tritium gas (90), alkylation with tritium (80,81) or carbon-14 labeled alkyl halides, borotritide reductions of aldehydes and ketones (80), and various ring syntheses with carbon-14 labeled precursors (47). The exchange procedures typically give low specific activities (50-300 mCi/mmol) and do not sitespecifically label the molecule.…”

The sunburn cell in mouse skin: preliminary quantitative studies on its production

“…If we suppose that in the provokation ofthe SBC the initial lesion is in DNA, the difference in its time course may be due to the differing types of DNA lesions in 254 nm alone and in 8-MOP photcscnsitization. Photosensitizing psoralens form photoadducts with pyrimidine bases of DNA (Rodighiero et al, 1970) and interstrand links between the DNA double helix (Cole, 1971); 254 nm UVR alone forms pyrimidine dimers and other lesions such as protein-DNA interaction (Smith, 1971). Interestingly, cyclophosphamide, a DNA cross-linking agent, seems to produce cells in the epidermis which, as illustrated by Milne (1972), resemble SBCs.…”

Structure specificity of polydeoxyribonucleotides for the photoreaction with psoralen

“…Psoralen and other furocoumarins photoreact with pyrimidine bases of DNA, bot in vitro and in vivo [1][2][3][4][5][6][7][8], under irradiation at long wavelength ultraviolet light. A C4-cycloaddition to the 5,6-double bond of pyrimidine bases occurs: furocoumarins can photoreact either with their 3,4-or 4',5'-double bond, forming therefore two types of photoadducts.…”