photodimerization

photodimerization

[¦fōd·ō‚dī·mə·rə′zā·shən]
(physical chemistry)
A bimolecular photochemical process involving an electronically excited unsaturated molecule that undergoes addition with an unexcited molecule of the same species.
References in periodicals archive ?
Splitting Cas9 into two segments (N-moiety: D2-V713 and C-moiety: S714-D1.368) and fusing each segment to a photodimerization domain (pMag and nMag) [84] resulted in reassociation of the two fragments on irradiation with blue light and restoration of Cas9 structure and activity, suggesting the possibility for optical regulation of Cas9 activity.
The top schematic shows an overview of the study, including photodimerization of the fluorescent AC monomer to the Di-AC particle mechanophore, followed by incorporation of the particles into a polyurethane matrix, with subsequent compression for the fluorescent mechanochemical activation.
To ensure that the presence of charged monomers would not interfere with the photo-cross-linking reaction of VBT moieties, irradiation studies have been performed on varying ratios of VBT-VBA copolymers to quantify the extent of their photodimerization and immobilization [8, 10].
It has been proposed [14] that the singlet excimer state is a precursor to the photodimerization of DNA bases and the excited state dimerization reaction occurs in competition with an internal conversion to the electronic ground state of nucleobases.
hospitals uses four techniques: photohydration, causing functional damage by inserting water into cellular structures; photosplitting, splitting the phosphate backbone of the DNA; photo crosslinking, creating bonds among protein molecules that lead to structural damage; and photodimerization, the bonding of the elements of DNA and RNA.
When the molecules of these materials--arranged in parallel stacking geometry--are exposed to ultraviolet light, they can undergo crystalline structure transformation as a result from photodimerization process [5].
This study demonstrates a unique approach to regio- and enantiocontrolled [2+2] photodimerization reactions in molecular crystals.
Part two contains chapters on cyclobutarenes; organometallic derivatives; synthesis and reactivity in the photochemistry of cyclobutanes; photodimerization of crystalline olefins in the solvent-free photosynthesis of cyclobutanes; chemistry of cubane and other prismanes; bicyclo[2.1.0]pentanes and bicyclo[2.2.0]hexanes; fluorinated cyclobutanes and their derivatives; cyclobutane pyrimidine dimmers as ultraviolet-induced DNA lesions; and cubanes, fenestranes, ladderanes, and other oligocyclobutanoids.
Work will continue on the synthesis of ligands for use in the production of new porous materials through solid state photodimerization of the vinyl groups.
In a nice twist, chiral, optically pure oxazolines on the periphery of the thiophenes control the self-assembly to give dimers of only one helical chirality, and this helical chirality controls the photodimerization to give essentially only one diastereomer (see opposite).