Synthesis and biological evaluation of the new ring system benzo[f]pyrimido[1,2-d][1,2,3]triazolo[1,5-a][1,4]diazepine and its cycloalkane and cycloalkene condensed analogues

Abstract

Derivatives of the new ring system benzo[f]pyrimido[1,2-d][1,2,3]triazolo[1,5-a][1,4]diazepinone and its cycloalkane and cycloalkene condensed analogues have been conveniently synthesized through a three-step reaction sequence.

Synthesis of Chiral Scaffolds Based on Polyfunctional Cyclobutane β‐Amino Acids

“…Now, in this work, we present the synthesis of β‐CBAAs containing an additional functional group (FG, Figure 1) linked to the amino acid through a flexible C 1 or C 2 spacer. As representative examples, a primary alcohol, a carboxylic acid, and a terminal alkyne have been chosen as targets because of their versatility to be transformed into different functions or for the coupling with other structural units via condensation processes or, in the case of alkynes, to be used in click chemistry [25] . Moreover, the terminal alkyne group has been discovered in natural products made by plants, fungi and microorganisms and, recently, a pathway for terminal‐alkyne amino acid biosynthesis has been reported [26] .…”

“…As representative examples, a primary alcohol, a carboxylic acid, and a terminal alkyne have been chosen as targets because of their versatility to be transformed into different functions or for the coupling with other structural units via condensation processes or, in the case of alkynes, to be used in click chemistry. [25] Moreover, the terminal alkyne group has been discovered in natural products made by plants, fungi and microorganisms and, recently, a pathway for terminal-alkyne amino acid biosynthesis has been reported. [26] Then, these amino acids have been utilized to prepare hybrid tripeptides providing polyfunctional chemical platforms suitable for building more elaborated compounds.…”

Synthesis of Alicyclic 2-Methylenethiazolo[2,3-b]quinazolinone Derivatives via Base-Promoted Cascade Reactions

“…20 Although the biological properties of thiazolo[2,3-b]quinazolinones have stimulated the development of a large number of synthetic methods to construct and decorate this moiety, there are fewer synthetic approaches towards the corresponding cyclic and alicyclic derivatives. Hence, in conjunction with our ongoing research on the study and modification of alicyclic -amino propargylamide deriva-tives through domino reaction procedures, 21,22 our present work is directed towards the syntheses of alicyclic 2-methylene-substituted thiazolo [2,3-b]quinazolinones. The synthetic process involves base-promoted cascade reactions of alicyclic -amino propargylamides or alicyclic ethyl 2-isothiocyanatocarboxylates, followed by investigations on retro-Diels-Alder (RDA) reactions of the norbornene derivatives.…”

“…Boc-protected amino acids 1a – 8a were prepared according to a literature procedure. 21 22 The propargyl-substituted alicyclic compounds 1b – 8b were prepared according to the procedure described in our previous work. 21 22 Column chromatography was performed using Merck silica gel (60 / 70–230 mesh ASTM).…”

“…21 22 The propargyl-substituted alicyclic compounds 1b – 8b were prepared according to the procedure described in our previous work. 21 22 Column chromatography was performed using Merck silica gel (60 / 70–230 mesh ASTM). Melting points were determined with a Hinotex-X4 micro melting point apparatus (Hinotek, Ningbo, China) and are uncorrected.…”