Nuclear magnetic resonance studies of cis-syn, trans-syn, and 6-4 photodimers of thymidylyl(3'-5')thymidine monophosphate and cis-syn photodimers of thymidylyl(3'-5')thymidine cyanoethyl phosphotriester

Journal Article · Tue Jul 26 04:00:00 EDT 1988 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00415a060· OSTI ID:6828116

Kan, L; Voituriez, L; Cadet, J

Three out of four possible photodimers of thymidylyl(3'-5')thymidine monophosphates (i.e., cis-syn, 6-4, and one of the trans-syn) and two structural isomers (i.e., R and S forms) of cis-syn-thymidylyl(3'-5')thymidine cyanoethyl phosphotriester have been isolated and purified from the reaction mixtures after UV irradiation and studied by multinuclear magnetic resonance spectroscopy. All five inter thymine base linked photodimers have grossly similar structures which are quite different from those of the parent thymidylyl(3'-5')thymidine. The base of Tp- is in the syn conformation, and that of -pT is in the anti conformation. The sugar puckering of Tp- is dominated by the /sup 2/E conformer, but in -pT it is in /sup 4/E; except for the conformer around the C/sub 5/'-O/sub 5/' bond, the 6-4 isomer is very similar to those of cis-syn and trans-syn conformation. As expected, there are sugar-phosphate backbone distortions in the phosphotriesters, due to the neutralization of the negative charge of the phosphate. In general the structures of all five photodimers are very close to those of the cis-syn photodimer of thymidylyl(3'-5')thymidine monophosphate cyanoethyl ester as studied by X-ray diffraction. While the trans-syn photodimer has two structural isomers, only one (C/sub 6/(of Tp-)-R) was produced by the UV irradiation and studied.

• Research Organization: Johns Hopkins Univ., Baltimore, MD (USA)
• OSTI ID: 6828116
• Journal Information: Biochemistry; (United States), Journal Name: Biochemistry; (United States) Vol. 27:15; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
AZINES
CARBON 13
CARBON ISOTOPES
CHEMICAL REACTIONS
CHEMICAL SHIFT
ELECTROMAGNETIC RADIATION
EVEN-ODD NUCLEI
FAR ULTRAVIOLET RADIATION
HETEROCYCLIC COMPOUNDS
ISOMERIZATION
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
MOLECULAR STRUCTURE
NMR SPECTRA
NUCLEAR MAGNETIC RESONANCE
NUCLEI
NUCLEOSIDES
NUCLEOTIDES
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHOSPHORUS 31
PHOSPHORUS ISOTOPES
PURIFICATION
PYRIMIDINE DIMERS
PYRIMIDINES
RADIATIONS
RESONANCE
RIBOSIDES
SPECTRA
STABLE ISOTOPES
THYMIDINE
ULTRAVIOLET RADIATION