First total synthesis of 6-tuliposide B

Labile (+)-6-tuliposide B, an antimicrobial compound produced by tulip, was synthesized in nine steps from d-glucose via the Baylis–Hillman reaction of 2-(tert-butyldimethylsilyloxy)-acetaldehyde with 6-O-acryloyl-1-O-(2-trimethylsilylethyl)-β-d-glucopyranoside, followed by a mild deprotection procedure using TFA in CH2Cl2.

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(+)-6-Tuliposide BC11H18O9[α]D = +37.7 (c 1.0, MeOH)Source of chirality: d-glucoseAbsolute configuration: (3′S)

(3′R)-epi-6-Tuliposide BC11H18O9[α]D = +30.9 (c 1.0, MeOH)Source of chirality: d-glucoseAbsolute configuration: (3′R)

1-O-(2-Trimethylsilylethyl)-6-O-[(3′S)-4′-(tert-butyldiethylsilyloxy)-3′-hydroxy-2′-methylenebutanoyl]-β-d-glucopyranosideC22H45O9Si2[α]D = −24.0 (c 1.0, CHCl3)Source of chirality: d-glucoseAbsolute configuration: (3′S)

1-O-(2-Trimethylsilylethyl)-6-O-[(3′R)-4′-(tert-butyldiethylsilyloxy)-3′-hydroxy-2′-methylenebutanoyl]-β-d-glucopyranosideC22H45O9Si2[α]D = −35.1 (c 1.0, CHCl3)Source of chirality: d-glucoseAbsolute configuration: (3′R)

(−)-Tulipalin BC5H6O3[α]D = −79.1 (c 0.25, MeOH)Source of chirality: 6-tuliposide BAbsolute configuration: (3S)

(+)-Tulipalin BC5H6O3[α]D = +79.4 (c 0.25, MeOH)Source of chirality: (3′R)-epi-6-tuliposide BAbsolute configuration: (3R)