Synlett 2010(14): 2156-2158  
DOI: 10.1055/s-0030-1258524
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

Practical Synthesis of the C-1027 Aminosugar Moiety

Keiichiro Hiraia, Yukio Tamuraa, Itaru Sato*b, Masahiro Hirama*a,b
Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
Research and Analytical Center for Giant Molecules, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
Fax: +81(22)7956566; e-Mail: isato@mail.tains.tohoku.ac.jp; e-Mail: hirama@mail.tains.tohoku.ac.jp;
Further Information

Publication History

Received 8 June 2010
Publication Date:
27 July 2010 (online)

Abstract

A concise and reliable synthetic route to the aminosugar moiety of the C-1027 chromophore was developed. The aminosugar moiety was synthesized from l-glutamic acid in 11 steps and 13% overall yield.

12

Selected Data for 9
Colorless needles; mp 162-164 ˚C (EtOAc); [α]D ²9 +8.6 (c 1.00, CH2Cl2). FT-IR (film): ν = 2944, 1742, 1458, 1275, 1179, 1114, 1041, 1014, 884, 801, 695 cm. ¹H NMR (400 MHz, CDCl3): δ = 0.94-1.15 (28 H, m, TIDPS), 1.45 (3 H, s, H6), 1.61 (3 H, s, H6), 2.53 (6 H, s, NMe2), 2.71 (1 H, d, J = 1.6 Hz, H4), 4.43 (1 H, d, J = 2.4 Hz, H2), 4.82 (1 H, dd, J = 2.4, 1.6 Hz, H3). ¹³C NMR (100 MHz, CDCl3): δ = 12.8, 13.3, 14.0, 14.3, 16.8, 16.9, 17.2, 17.2, 17.3, 17.6, 17.6, 17.9, 25.7, 24.6 (C6), 31.4 (C6), 45.0 (NMe2), 68.7 (C4), 71.8 (C3), 76.7 (C2), 87.4 (C5), 169.3 (C1). ESI-HRMS: m/z calcd for C21H43NNaO5Si2 + [M + Na+]: 468.2572; found: 468.2575.

13

Selected Data for 2
Colorless oil; [α]D ²7 -19.0 (c 1.00, CHCl3). FT-IR (film): ν = 3386, 2867, 1465, 1386, 1364, 1248, 1137 cm. ¹H NMR (400 MHz, CDCl3): δ = 1.03-1.13 (28 H, m, TIPDS), 1.30 (3 H, s, H6), 1.60 (3 H, s, H6), 2.46 (1 H, d, J = 2.4 Hz, H4), 2.55 (6 H, s, NMe2), 2.76 (1 H, br s, OH), 3.49 (1 H, dd, J = 8.0, 3.2 Hz, H2), 4.73 (1 H, dd, J = 3.2, 2.4 Hz, H3), 5.01 (1 H, br d, J = 8.0 Hz, H1). ¹³C NMR (100 MHz, CDCl3):
δ = 13.0, 13.1, 13.3, 13.6, 14.4, 17.1, 17.1, 17.4, 17.4, 17.5, 17.5, 17.6, 23.7 (C6), 30.8 (C6), 44.5 (NMe2), 69.4 (C4), 74.8 (C3), 78.1 (C2), 78.4 (C5), 90.5 (C1). ESI-HRMS:
m/z calcd for C21H46NO5Si2 + [M + H+]: 448.2909; found: 448.2910.