Tianpa You

Microwave-assisted and Efficient One-Pot Synthesis of Substituted 1,2,4-Triazoles

An efficient microwave-assisted one-pot and three-component synthesis of substituted 1,2,4-triazoles has been achieved utilizing substituted primary amines.

Ring‐Expanded C‐Nucleoside Analogues of Tiazofurin

Abstract Novel 1,3‐dioxane C‐nucleoside analogues of tiazofurin 2‐[2‐(hydroxymethyl)‐1,3‐dioxan‐5‐methyl‐5‐yl] 1,3‐thiazole‐4‐carboxamide, 2‐[2‐(hydroxymethyl)‐1,3‐dioxan‐5‐ethyl‐5‐yl] 1,3‐thiazole‐4‐carboxamide and 2‐[5‐(hydroxymethyl)‐1,3‐dioxan‐5‐methyl‐2‐yl] furan, 2‐[5‐(hydroxymethyl)‐1,3‐dioxan‐5‐methyl‐2‐yl] thiophen have been synthesized from DMPA and DMBA. Their conformational characteristics have been investigated.

Asymmetric Synthesis of β‐DDB Through Oxazoline‐Mediated Ullmann Coupling

Abstract Biphenyl lignan (β‐DDB) (2), an effective drug in the treatment of hepatitis, was for the first time asymmetrically synthesized via a chiral oxazoline mediated Ullmann coupling. The two enantiomers of β‐DDB have been obtained in this way by using the optically pure amino alcohols L‐valinol and D‐valinol, respectively. However, attempts to synthesize enantiopure α‐DDB (1) by the same method failed because of the racemization of 1 at room temperature in solution.

Novel Route for Preparation of 7‐Methyl‐camptothecin and Its Possible Mechanism

Abstract A novel route for preparation of 7‐methyl‐camptothecin is described. Its possible mechanism is discussed.

Convenient Preparation of Chiral trans-9,10-Dihydrophenanthrene-9,10-diamine

Abstract Chiral trans-9,10-dihydrophenanthrene-9,10-diamine was conveniently prepared from biphenyl-2,2′-dialdehyde using intramolecular imino pinacol coupling and oxidative cleavage of aminoalcohol as key steps.

A Convenient Preparation of Enantiopure endo‐2‐Hydroxyepicamphor and endo‐3‐Hydroxycamphor from Camphoric Acid

Abstract From easily available camphoric acid, endo‐2‐hydroxyepicamphor 1 and endo‐3‐hydroxycamphor 2 have been prepared as a mixture which can be further separated to pure forms. This method offers a convenient synthesis of 1 and 2.

Synthesis of ribavirin analogues containing amino-acid residues

Abstract A convenient procedure for coupling 1,2,3,5‐tetra‐O‐acetyl‐β‐D‐ribofuranose and 4‐nitroimidazole was developed to obtain β‐anomer as the major product. A novel category of nucleoside analogues with the introduction of natural L‐amino acids to the base moiety were designed and synthesized to develop selective and effective antiviral agents.