ChemInform Abstract: Synthesis of Steroidal 1,5‐Benzothiazepine Derivatives.

Ultrasound-assisted synthesis of benzothiazepines and assessment of theirin vitroacetylcholinesterase inhibition activity

“…In the 13 C NMR spectrum of compound 4, the signals appearing between δ 113.1 and 143.1 ppm attributed to aromatic carbons while the carbon of C = N appeared at δ 167.5 ppm clearly indicated the formation of C = N which also supports the formation of compound 4. The spectral studies are in agreement with the possible structures (4 and 4a), but the proposed mechanism (50-52), IR bands, and the absence of NH grouping signal in the 1 H NMR (50)(51)(52), superimposed IR, and co thin layer chromatography (TLC) with authentic sample prepared according to literature methods. It is well documented that the formation of 1,5-benzothiazepines occurs by the reaction of α,β-unsaturated ketones and 2-aminothiophenol under acid-catalyzed conditions.…”

“…The formation of 8 was assumed to proceed through the Micheal addition of sulfur in o-aminophenol on the δ-carbon double bond followed by intramolecular cyclization of -NH 2 on β-carbon atom of the unsaturated ketone (Scheme 2). All the spectral and analytical data for 4, 5, 6, and 8 are identical to those previously reported given in references [50][51][52] and supplemental material. 13 C NMR spectral data of titled compounds are reported for first time.…”

“…The benzothiazepines (4-6 and 8) are identified on the basis of physical, microanalytical (Supplemental material, Table S1), spectral (IR, 1 H NMR, and mass spectrometry [MS]) data, and comparison with authentic sample is given in the SI (50)(51)(52). This procedure provides a much more efficient and practical synthesis of the title compounds with the following advantages: significant shortening of the reaction time, higher yield, and ecofriendly as compared to the conventional methods.…”

Synthesis of steroidal [4,6-b,c]-benzothiazepines, a new class of aromatase inhibitor

“…The 4P configuration is then indicated by the 13c resonance position of C-2, which shows a y-gauche upfield shift of -3.5 ppm from the position of C-2 in corresponding C-4-unsubstituted steroids (9); the C-19 resonance position (3.6 ppm downfield from that of corresponding C-4-unsubstituted steroids (9)); and the appearance of the C-4 hydrogen resonance at 6 4.06 ppm as narrow doublet of doublets (J= 3.8 and 3.2 Hz), indicating the presence of only axial-equatorial couplings to hydrogens at C-3 and C-5. Michael addition to 5 from the axial (4P) side is predictable on stereoelectronic grounds (10) and is in accord with literature precedent (1 1): the 401 stereochemistry assigned earlier to similar products was based on "expectation" and is not substantiated by spectral data (7).…”

Synthesis of optically active 1,5-benzothiazepines

“…In the case of this optically active 1,5-benzothiazepine, the source of the chirality was the sugar used as building block. 74 Mushfiq et al [75][76][77] synthesized optically active 1,5-benzothiazepines condensed with a steroid skeleton. Steroid derivatives 67 bearing an α,β-unsaturated ketone unit were allowed to react with 2-aminothiophenol (1) to afford the benzothiazepine derivatives 68 (Scheme 18).…”