Effective strategy for conformer-selective detection of short-lived excited state species: Application to the IR spectroscopy of the N1H keto tautomer of guanine
Effective strategy for conformer-selective detection of short-lived excited state species: Application to the IR spectroscopy of the N1H keto tautomer of guanine
复制标题
短寿命激发态物种构象异构体选择性检测的有效策略：在鸟嘌呤 N1H 酮互变异构体红外光谱中的应用
DOI：
10.1021/acs.jpca.6b01194
复制
发表时间：
2016
影响因子：
2.9
通讯作者：
and M. Mons
中科院分区：
文献类型：
--
作者：
H. Asami;M. Tokugawa;Y. Masaki;S. Ishiuchi;E. Gloaguen;K. Seio;H. Saigusa;M. Fujii;M. Sekine;and M. Mons
生物分子激发态的超快失活过程，如最稳定的鸟嘌呤互变异构体，禁止任何最先进的气相光谱研究这些物种与纳秒激光。这个缺点可以通过将具有长寿命激发态的发色团接枝到感兴趣的分子上来克服，从而允许通过纳秒R2 PI进行质量选择性检测，并因此允许双共振IR/UV共形选择性光谱研究。目前的原则是证明酮形式的修饰的9-甲基鸟嘌呤，其中的IR/UV双共振光谱中的C = O伸缩区域，报告的第一次，广泛的振动耦合内的鸟嘌呤部分提供了证据。这样一个成功的策略开辟了一条路线，以质量选择性红外/紫外光谱研究的分子表现出天然发色团具有超短寿命的激发态，如DNA碱基，其复合物以及含有短寿命的芳香族残基的肽。
The ultrafast deactivation processes in the excited state of biomolecules, such as the most stable tautomers of guanine, forbid any state-of-the-art gas phase spectroscopic studies on these species with nanosecond lasers. This drawback can be overcome by grafting a chromophore having a long-lived excited state to the molecule of interest, allowing thus a mass-selective detection by nanosecond R2PI and therefore double resonance IR/UV conformer-selective spectroscopic studies. The principle is presently demonstrated on the keto form of a modified 9-methylguanine, for which the IR/UV double resonance spectrum in the CO stretch region, reported for the first time, provides evidence for extensive vibrational couplings within the guanine moiety. Such a successful strategy opens up a route to mass-selective IR/UV spectroscopic investigations on molecules exhibiting natural chromophores having ultrashort-lived excited states, such as DNA bases, their complexes as well as peptides containing short-lived aromatic residues.