Efficient Synthetic Route to Ravidosamine Derivatives

Abstracts

Concise synthesis of ravidosamine, the amino sugar constituent of ravidomycin and other antibiotics, has been achieved. The key steps include (1) regioselective reduction of benzylidene acetal with DIBAL, and (2) stereoselective reduction of oxime to the corresponding amine by using samarium diiodide in the ­presence of methanol.

ravidosamine - regioselectivity - boron trifluoride etherate - stereoselectivity - samarium diiodide - amino sugar

References

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Compound 18: ¹H NMR (400 MHz, CDCl₃): δ = 7.40-7.26 (m, 10 H), 4.86 (d, J = 11.2 Hz, 1 H), 4.78 (d, J = 3.7 Hz, 1 H), 4.64-4.56 (m, 3 H), 4.07 (dd, J = 3.7, 11.2 Hz, 1 H), 3.85 (br q, J = 6.6 Hz, 1 H), 3.62 (br d, J = 2.9 Hz, 1 H), 3.33 (s, 3 H), 3.00 (dd, J = 2.9, 11.2 Hz, 1 H), 2.59 (s, 6 H), 1.13 (d, J = 6.6 Hz, 3 H). ¹³C NMR (100 MHz, CDCl₃): δ = 138.2 (C), 138.1 (C), 128.2 (CH), 128.1 (CH), 128.0 (CH), 127.9 (CH), 127.5 (CH), 127.4 (CH), 97.2 (CH), 82.9 (CH), 75.2 (CH₂), 75.1 (CH), 71.1 (CH₂), 66.8 (CH), 61.4 (CH), 54.9 (CH₃), 43.5 (CH₃), 16.3 (CH₃). IR (neat): 3030, 2931, 2895, 1454, 1099, 1053, 733, 696 cm^-1.

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