A catalyst-free, simple and green protocol has been accomplished for the synthesis of novel 1H-furo[2,3-c]pyrazole-4-amines in a one-pot four-component domino reaction involving hydrazines, ethyl acetoacetate, aromatic amines and phenylglyoxal monohydrate in water. The protocol presented herein describes in situ generated pyrazolone as intermediate reactants with phenylglyoxal monohydrate in a Knoevenagel
ONE-FLASK SYNTHESES OF SOME NEW SPIROTHIAZOLOPYRANOPYRAZOLE, SPIROTHIAZOLODIHYDROPYRIDI-NOPYRAZOLE AND SPIROTHIAZOLOTHIOPY-RANOPYRAZOLE DERIVATIVES AS ANTIMICROBIAL AGENTS
作者:Abdullah A. Al-ahmadi
DOI:10.1080/10426509708043500
日期:1997.3.1
(1a-f) in a mixture of ethanol/pyridine at reflux temperature to give spirothiazolopyranopyrazoles (3a-l) in one flask. The fusion of compounds 1a-f with 2a and/or 2b in the presence of ammonium acetate afforded spirothiazolodihydropyridinopyrazole derivatives (4a-l) in good yields. Also the reaction of compounds 1a-f with 2a and/or 2b with phosphoruspentasulfide in pyridine at reflux temperature yielded
complex nature of pain mechanisms. Some important receptors include cannabinoid (CB1 and CB2) imidazoline-2 (I2), adenosine, purinergic (P2X3 and P2X7), transient receptor potential vanilloid (TRPV) and ankyrin (TRPA) and neurotransmitters such as bradykinin, prostaglandin E2, tumor necrosis factor alpha (TNF-α), interleukin (IL)-1 and nitric oxide. Soluble epoxide hydrolase (eSH), cyclooxygenase-2