5,6,7,8-Tetrahydroquinolines. 5. Antiulcer and antisecretory activity of 5,6,7,8-tetrahydroquinolinethioureas and related heterocycles

Abstract

A series of thioureas derived from 5,6,7,8-tetrahydroquinoline, 1,5-, 1,6-, and 1,8-naphthyridiness, pyrido[2,3-b]azepine, and 7-azaindoline has been prepared and tested for antisecretory activity in the pylorus-ligated rat and protective activity against gastric erosions caused by cold-restraint stress. The thioureas exhibit different structure-activity relationships from the corresponding 5,6,7,8-tetrahydroquinoline-8-thiocarboxamides and these relationships are discussed. The activity of the thioureas is less affected by structural differences than the corresponding thioamides although they probably have the same mode of action.

An Expeditious and Efficient Synthesis of Highly Functionalized [1,6]-Naphthyridines under Catalyst-Free Conditions in Aqueous Medium

“…Previous synthesis of these heterocycles mostly relied upon annulation of a pyridine ring ,,, onto a 4-piperidone or equivalent or reductions or reductive additions to the fully aromatized 1,6-naphthyridine system. , The approach to naphthyridines presented herein offers for the first time an unprecedented coupling of methyl ketones, amines, and malononitrile which leads to the construction of the nitrogen-containing ring during the synthesis without starting from any nitrogen-containing heterocycle moiety. Thus, from a practical point of view, the newly developed protocol is significant proof of the fact that nitrile is one of the most versatile functional groups as it can be readily transformed into various other functional groups or reactive intermediates.…”

Synthesis and characterization of some novel coumarin based various 2-aryl-pyrido [3,2-c] coumarins

“…The pyrido [2,3-c]coumarin skeleton constitutes the backbone of Santiagonamine [8] . This alkaloid has been isolated from Berberis Darvinii (Berberidaceae) and has shown interesting wound healing properties [9][10][11][12][13][14][15] . Thus pyrido fused coumarins become an important class of heterocyclic fused coumarin derivatives and therefore brief literature account on various synthetic methods available for pyrido fused coumarins are presented in research work…”

Synthesis of Novel Fluorinated 11H-Azaindolo[3,2-c]isoquinolines

“…Pyrrolo[2,3‐ b ]pyridines also known as azaindoles have received significant synthetic importance as they have been used as various pharmaceutical and antipsychotic agents . Tetracyclic ring systems similar to indoloquinolines and indoloisoquinolines have received considerable synthetic importance because of their interesting biological properties such as anti‐inflammatory, antitumor, antibacterial, and fungicidalactivities .…”