Synthesis and progesterone receptor binding affinity of substituted 1-phenyl-7-benzyl-4,5,6,7-tetrahydro-1-indazoles

Five‐Membered Heterocycles: 1,2‐Azoles. Part 1. Pyrazoles

“…The reaction needs a slightly acidic medium to catalyze the conversion of the ketone into the hydrazone and it is imperative the use of a Dean-Stark apparatus to eliminate the water, to avoid mesylate hydrolysis to the corresponding phenol, which does not cyclize to indazoles under these reaction conditions. and hexahydro-1H-and 2H-indazole derivatives are also obtained from the reaction of appropriate chalcone-type compounds or b-diketones with hydrazine derivatives [283,284,[286][287][288].…”

“…These tetrahydroindazoles(317) are oxidized to 2-substituted-2H-indazoles 318 by treatment with DDQ (Scheme 8.96)[283]. 3-Substituted-1-aryl-4,5,6,7-tetrahydro-1H-indazoles 320 are obtained by the reaction of diketone 319 with arylhydrazines (Scheme 8.97)[284]. Various 4,5-dihydro-1H-benzo[g]indazole-based ligands for cannabinoid receptors have been prepared by a similar procedure[285].…”

Ethyl 4-(3-chlorophenyl)-3,6-dihydroxy-6-methyl-2-(2-pyridyl)-4,5,6,7-tetrahydroindazole-5-carboxylate

“…For the synthesis and stereochemistry investigations through NMR of N(2)-pyridyl tetrahydroindazoles, see: Amirthaganesan et al (2008). For the biological activity of tetrahydroindazoles, see: Connolly et al (1997). For ring conformational analysis, see: Cremer & Pople (1975);Nardelli (1983).…”

“…In azole family, tetrahydroindazoles (cycloalkane derivatives of pyrazoles) are having much importance for their effective biological potencies (Connolly et al, 1997). Our current research work is focused on the stereospecific synthesis of 1 (H) and various N-substituted tetrahydroindazoles by taking cyclic β keto esters as an effective synthons, and exploring their stereochemistry.…”

Efficient Microwave-Assisted Synthesis of Tetrahydroindazoles and their Oxidation to Indazoles

“…1 Their wide variety of applications in medicinal chemistry can be illustrated by their use as pharmaceutical agents in fields such as CNS disorders (e.g., granisetron), 2 anti-inflammatory (e.g., bendazac and benzydamine) 2,3 and antimicrobial agents, 4 anti-HIV protease inhibition, 5 anti-tumour 6 and nitric oxide synthase inhibitors 7,8 and binding affinity of non-steroidal progesterone receptor. 9 Structural modifications of the anti-inflammatory agent bendazac have been carried out and, in some cases, the synthesised compounds showed analgesic effects along with anti-inflammatory properties. 10 There are several methods for the synthesis of indazoles; 1,11 most of them start from benzene derivatives, where the pyrazole ring is formed by ring closure.…”