The N–N bond as a chiral axis: 3-diacylaminoquinazolinones as chiral acylating agents

Understanding Conformational Preferences of Atropisomeric Hydrazides and Its Influence on Excited State Transformations in Crystalline Media

“…An important and unique feature shown by hydrazides in crystalline media relates to the pyramidalization of the nitrogen atom [10,11,12,13,14,15,16,17,18,19,20,21,22]. There have been few reports in the literature on the single crystal XRD analysis of N – N bond based compounds that shed light on this unusual feature and describe such hydrazides as atypical compounds.…”

2‐Amino[1,2,4]triazolo[1,5‐c]quinazolines and Derived Novel Heterocycles: Syntheses and Structure–Activity Relationships of Potent Adenosine Receptor Antagonists

“…13 C NMR spectra were recorded for selected compounds from each subfamily only, or if necessary for structural assignment. Starting materials 22 b , 22 i , 22 o , 22 p , 22 q , 26 , 28 , and 30 were prepared according to published procedures. Syntheses of products 11 b , 11 n ,, 12 b , 13 a , 13 b , 15 b , and 16 b were previously reported.…”

Regioselective synthesis of 6-trifluoromethyl-1,4,5,6-tetrahydropyrazolo[3,4-b]pyran derivatives

“…In recent years, the synthesis of fluorinated Oheterocyclic or N-heterocyclic compounds have draw much attention [4][5][6]. The b-ketoesters are well established as synthetic intermediates in heterocyclic chemistry [7]. The literature has reported a series of CF 3 -substituted pyridines, pyrazoles and pyrans and their derivatives, which were prepared from the reactions of trifluoromethyl-1, 3-dicarbonyl compounds as fluorine-containing building-blocks [8][9][10].…”