Photophysical and Photochemical Properties of 4-Thiouracil: Time-Resolved IR Spectroscopy and DFT Studies

	Photophysical and Photochemical Properties of 4-Thiouracil: Time-Resolved IR Spectroscopy and DFT Studies
	Zou, Xiaoran; Dai, Xiaojuan; Liu, Kunhui; Zhao, Hongmei; Song, Di; Su, Hongmei
刊名	journal of physical chemistry b
	2014-06-05
卷号	118 期号:22 页码:5864-5872
英文摘要	intensified research interests are posed with the thionudeobase 4-thiouracil (4-tu), due to its important biological function as site-specific photoprobe to detect rna structures and nucleic acid-nucleic acid contacts. by means of time-resolved ir spectroscopy and density functional theory (dft) studies, we have examined the unique photophysical and photochemical properties of 4-tu. it is shown that 4-tu absorbs uva light and results in the triplet formation with a high quantum yield (0.9). under n-2-saturated anaerobic conditions, the reactive triplet undergoes mainly cross-linking, leading to the (5-4)/(6-4) pyrimidine-pyrimidone product. in the presence of o-2 under aerobic conditions, the triplet 4-tu acts as an energy donor to produce singlet oxygen o-1(2) by triplet-triplet energy transfer. the highly reactive oxygen species o-1(2) then reacts readily with 4-tu, leading to the products of uracil (u) with a yield of 0.2 and uracil-6-sulfonate (u-so3) that is fluorescent at similar to 390 nm. the product formation pathways and product distribution are well rationalized by the joint b3lyp/6-311+g(d,p) calculations. from dynamics and mechanistic point of views, these results enable a further understanding for 4-tu acting as reactive precursors for photochemical reactions relevant to o-1(2), which has profound implications for photo cross-linking, dna photodamage, as well as photodynamic therapy studies.
WOS标题词	science & technology ; physical sciences
类目[WOS]	chemistry, physical
研究领域[WOS]	chemistry
关键词[WOS]	excited-state dynamics ; fluorescence up-conversion ; ultrafast internal-conversion ; transfer ribonucleic-acids ; photo-cross-linking ; escherichia-coli ; conical intersections ; nucleic-acids ; transfer-rna ; 4-thiouridine
收录类别	SCI
语种	英语
WOS记录号	WOS:000337011400007
公开日期	2016-05-09
内容类型	期刊论文
源URL	[http://cas-ir.dicp.ac.cn/handle/321008/145677]
专题	大连化学物理研究所_中国科学院大连化学物理研究所
作者单位	Chinese Acad Sci, Inst Chem, BNLMS, State Key Lab Mol React Dynam, Beijing 100190, Peoples R China
推荐引用方式 GB/T 7714	Zou, Xiaoran,Dai, Xiaojuan,Liu, Kunhui,et al. Photophysical and Photochemical Properties of 4-Thiouracil: Time-Resolved IR Spectroscopy and DFT Studies[J]. journal of physical chemistry b,2014,118(22):5864-5872.
APA	Zou, Xiaoran,Dai, Xiaojuan,Liu, Kunhui,Zhao, Hongmei,Song, Di,&Su, Hongmei.(2014).Photophysical and Photochemical Properties of 4-Thiouracil: Time-Resolved IR Spectroscopy and DFT Studies.journal of physical chemistry b,118(22),5864-5872.
MLA	Zou, Xiaoran,et al."Photophysical and Photochemical Properties of 4-Thiouracil: Time-Resolved IR Spectroscopy and DFT Studies".journal of physical chemistry b 118.22(2014):5864-5872.