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Updated: Jul 18, 2025

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
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在生物系统中模拟分子光开关的热异构

Amirhossein Bakhtiiari1, Gustavo J Costa1, Ruibin Liang1

  • 1Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, United States.

Journal of chemical theory and computation
|August 22, 2023
PubMed
概括

分子光开关,如光静止剂 (PST),使光控制药物治疗成为可能. 精确模拟它们在生物环境中的热异构,特别是使用明确溶剂,是预测药物性能和设计新型光调节药物的关键.

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Photochemical Electrocyclic Reactions: Stereochemistry

The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
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The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
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