Premium
PHOTOCHEMICAL EXCHANGE REACTIONS OF THYMINE, URACIL AND THEIR NUCLEOSIDES WITH SELECTED AMINO ACIDS
Author(s) -
Shetlar Martin D.,
Taylor John A.,
Hom Kellie
Publication year - 1984
Publication title -
photochemistry and photobiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.818
H-Index - 131
eISSN - 1751-1097
pISSN - 0031-8655
DOI - 10.1111/j.1751-1097.1984.tb04591.x
Subject(s) - chemistry , thymine , hexanoic acid , decarboxylation , uracil , photochemistry , amino acid , glycine , deamination , alanine , stereochemistry , organic chemistry , dna , biochemistry , catalysis , enzyme
The photoinduced exchange reactions of thymine with lysine at basic pH, using 254 nm light, have been studied. Three products have been isolated, namely, 6‐amino‐2‐(1‐thyminyl)hexanoic acid ( Ia ), 2‐amino‐6‐(1‐thyminyl)hexanoic acid ( IIa ) and 1‐amino‐5‐(1‐thyminyl)pentane ( IIIa ). Compound IIIa was shown to be a secondary product, produced by photochemical decarboxylation of Ia . Photochemical reaction of thymine with glycine and alanine at basic pH led, respectively, to formation of 2‐(1‐thyminyl)acetic acid ( Ic ) and 2‐(1‐thyminyl)propionic acid ( Id ). Compounds Ic and Id underwent photolysis to produce the decarboxylated secondary products 1‐methylthymine and 1‐ethylthymine, respectively. Thymidine reacts photochemically with glycine and alanine to produce the same products. Irradiation of DNA in the presence of lysine at basic pH led to the formation of the same products formed in the thymine‐lysine system, namely Ia , IIa and IIIa . Uracil was found to undergo analogous photochemical exchange reactions with lysine to form 6‐amino‐2‐(1‐uracilyl) hexanoic acid ( Ib ), and 2‐amino‐6‐(1‐uracilyl)hexanoic acid ( IIb ). Compound Ib was found to undergo photodecarboxylation to form 1‐amino‐5‐(1‐uracilyl)pentane ( IIIb ), analogous to the secondary photoreaction of Ia . Photoreaction of uracil with 1,5‐diaminopentane (cadaverine) likewise led to formation of IIIb .