Synthesis of New Steroidal Oxazoles and Thiazoles.

Abstract

Synthesis of New Steroidal Oxazoles and Thiazoles. -Some new steroidal oxazoles (III) and thiazoles (V) are synthesized by a simple condensation of steroidal α-bromoketones (I) with urea and thiourea, respectively. -(SHAMSUZZAMAN*; SALIM, A.; AKRAM, M. K.; SALEEM, K.; SIDDIQUI, N.; Indian J. Chem., Sect.

Eco-friendly synthesis, physicochemical studies, biological assay and molecular docking of steroidal oxime-ethers

“…Comparative results of previously reported compounds ( 5 and 6 ) in terms of yield and reaction period are given. All spectral and analytical data for compounds 5 and 6 were identical with those previously reported (Shamsuzzaman et al, 2003[ 22 ]). Comparison of conventional and microwave syntheses of 4 - 6 : (1) conventional procedure reported (Shamsuzzaman et al, 2003[ 22 ]); compound 5 , yield: 90 %, time: 1 h, compound 6 , yield: 85 %, time: 1 h, (2) microwave procedure; compound 4 , yield: 85 %, time: 2.5 min, compound 5 , yield: 93 %, time: 2.0 min, compound 6 , yield: 90 %, time: 3.0 min, respectively.…”

“…Microwave-promoted reactions were carried out using a Laboratory Grade Microwave oven fixed with a temperature monitoring sensor. Steroidal keto-oximes (1-3) were prepared according to published methods (Shamsuzzaman et al, 2003[ 22 ]; Soppee et al, 1964[ 24 ]).…”

“…( Z )-3β-Acetoxy-7-(2′-aminoethoxyimino)- cholest-5-ene ( 5 ): mp 150-151 ºC; IR and 1 H NMR: see ref. (Shamsuzzaman et al, 2003[ 22 ]); 13 C NMR (100 MHz, CDCl 3 ): δ 170.1, (OCOCH 3 ), 168.3 (C7), 153.9 (C5), 114.1 (C6), 71.0 (C3), 69.7 (OCH 2 ), 55.6 (NCH 2 ), and other 13 C NMR signals are in close accordance with those of compound 4 . EI-MS ( m/z ): 500 [M] +• , 441 [M-OCOCH 3 ] + , 440 [M-OCH 2 CH 2 NH 2 ] + , 387 [M-C 8 H 17 ] + .…”

“…Synthetic steroidal dioxime-ethers exhibited neuromuscular blocking activity (Garcia et al, 1980[ 14 ]). However, some new steroidal oxime-ethers (ω-hydroxyalkyl oximes) (Slavikova et al, 1998[ 25 ]), aminoethoxy oximes (Shamsuzzaman et al, 2003[ 22 ]; Sharma et al, 2011[ 23 ]) have also been synthesized without assay of any biological activities. It has been found that the cytotoxicity of substituted hydroximino steroid is governed by the position of the hydroximino group as well as the nature of the side chain in the steroidal moiety (Cui et al, 2009[ 11 ]).…”

A Facile Synthesis of 6,7-Fused Steroidal Thiazoles via 1,3-Intramolecular Migration of Bromine/Allylic Displacement of Bromine

“…Ahmad 38 has reported a similar set of title compounds starting from the same material but with a different solvent, methanol but provided no satisfactory mechanism. However, Shamsuzzaman et al 39 reported different steroidal thiazoles starting from similar precursor using ethanol as a solvent with a refluxing period of 2-3 hrs. …”