Synthesis 2006(20): 3405-3408  
DOI: 10.1055/s-2006-950213
PAPER
© Georg Thieme Verlag Stuttgart · New York

An Unexpected Formation of 2-Aryl-3-benzyl-1,3-thiazolidin-4-ones

Wilson Cunico*, Liliane R. Capri, Claudia R. B. Gomes, Rosangela H. Sizilio, Solange M. S. V. Wardell
FioCruz - Fundação Oswaldo Cruz, Instituto de Tecnologia em Fármacos, FarManguinhos R. Sizenando Nabuco, 100 Manguinhos, Rio de Janeiro 21041-250, RJ, Brazil
e-Mail: wjcunico@far.fiocruz.br;
Further Information

Publication History

Received 23 May 2006
Publication Date:
21 August 2006 (online)

Abstract

The reactions of l-valine, arenealdehydes, mercaptoacetic acid and DIPEA produce 2-aryl-3-benzyl-1,3-thiazolidin-4-ones with moderate yields (48-65%). Characterization of the 1,3-thiazolidin-4-ones was achieved by NMR and confirmed by X-ray crystallography.

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Selected data for 2-(2-nitrophenyl)-1,3-oxathiolan-5-one (4b): 1H NMR (500 MHz, CDCl3): δ = 8.35 (dd, J HH = 8.0 Hz, 2 J HH = 2.0 Hz, 1 H), 8.27 (d, J HH = 8.0 Hz, 2 J HH = 1.0 Hz, 1 H), 7.81 (d, J HH = 7.5 Hz, 1 H), 7.63 (dd, J = 8.0 Hz, 1 H), 6.55 (s, 1 H, H2), 3.93 (d, H4a, J HH = 16.5 Hz, 1 H), 3.82 (d, H4b, J HH = 16.5 Hz, 1 H); 13C NMR (125 MHz, CDCl3): δ = 171.7 (C=O), 148.4, 138.8, 132.3, 130.1, 124.7, 121.6 (Ph), 80.6 (C2), 32.7 (C4); CG-MS: m/z (%) = 225 (10) [M], 152 (100), 105 (20), 74 (70), 51 (25).

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X-ray crystal data for 3e; CCDC 603430; Empirical formula C16H11F2NOS; Formula weight 302.81; T = 120 K; λ = 0.71073 Å; Crystal system = monoclinic; Space group P21/a; Unit cell dimensions a = 10.1491 (4), b = 10.1236 (3), c = 13.9981 (6) Å, β = 106.333 (2)°; V = 1380.20 (9) Å3; z-2; D = 1.457 gcm-3; µ = 0.254 mm-1; Theta range for data collection 1.52° to 27.45°; Reflections collected 15114; Independent reflections 3128 [R(int) = 0.0340]; Refinement method Full-matrix least-squares on F2; R1 = 0.0680, wR2 = 0.1729 [I>2σI]. Structure solution and refinement were achieved using SHELX97 and SHELXL97 (Sheldrick, G. M. SHELXS97 and SHELXL97, University of Göttingen, Germany, 1997).