1. Hzdd, J. =. , 1. , and J. =. , p-Nitrophenyl ?-D-galactofuranosyl-(1?6)-?-D-galactopyrano- side (18) TLC: R f = 0, m, 3H, 5b-H, 6a-H, 6?a-H), 3.45 (dd, 1H, J = 4.4, 11.7 Hz 98.5 (1b-C)6b-C) ppm. HRMS (ESI ?mol) in the presence of 4800 U of Araf51, and was isolated in 25% yield (7.6 mg, pp.9596-9599

1. Hz and J. =. , (6b-CH 2 ) ppm. p-Nitrophenyl ?-D-galactofuranosyl-(1?4)-?-D-mannopyrano- side (20) This compound was obtained according to the general procedure by incubation of 1 (10 mg, 33 ?mol) with mannopyranosidic acceptor 7 (100 mg, 330 ?mol) in the presence of 2400 U of Araf51, and was isolated in 49% yield (7.5 mg) TLC: R f = 0, ) ppm. 13 C NMR (125 MHz, D 2 O): ? = 160.7 (Cipso C 6 H 4 ), 142.0 (Cp C 6 H 4 ), 126.0 (Cm C 6 H 4 ), pp.91-94

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