| Nitrogen-containing heterocycles are structural units of many natural products and biologically active drugs.Most small-molecule drugs contain at least one nitrogen heterocycle.As an important member,1,4-dihydropyridine structure is found in the active molecules such as the dipine-like drugs for the treatment of hypertension and the reduced coenzyme I(NADH)and II(NADPH).Since the 1,4-dihydropyridine was firstly synthesized by Hantzsch in the 1880 s,researches based on it have sprung up.The work in this dissertation is also about it.The content of this dissertation is divided into five parts: The first part mainly introduces the synthesis of 1,4-dihydropyridines and their applications in organic chemistry as well as the method of hydrogen isotope exchange(HIE).1,4-dihydropyridines are mainly used as hydrogen and alkyl donors participating in the reduction,alkylation and cross-coupling reactions.The existing HIE methods are mainly three kinds: acid/base-mediated method,homogeneous catalysis and heterogeneous catalysis.The second part is mainly about the alkylation of heterocycles with 1,4-dihydropyridines as alkyl precursors.The alkyl radical generated by 1,4-dihydropyridine under light irridiation is added to the heterocyclic substrate such as 4-hydroxyquinazoline,the resulting intermediate was then oxidized by air to obtain a final alkylated product,such as 2-cyclohexyl-4-hydroxyquinazoline.The reaction conditions are mild,the efficiency is high,and the raw materials are cheap and easy to obtain.The third part mainly introduces the deuteration of 1,4-dihydropyridines.Under the acidic and heating conditions,the hydrogen isotope exchange occurs selectively at the C-H bond in the 2,6-position alkyl groups.The fourth part mainly introduces the synthesis of some representative raw materials and the general operation steps of the main experiments.The fifth part mainly introduces the summary of the full text and the prospects for the application of related methods. |
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