Synthesis of simplified analogues of eleutherobin via a Claisen rearrangement/RCM strategy

The enantioselective synthesis of a number of simplified analogues of the cytotoxic natural product eleutherobin is reported.

The enantioselective synthesis of a number of simplified analogues of the cytotoxic natural product eleutherobin is reported.Figure optionsDownload as PowerPoint slide

(5Z,8S,9R)-8-(tert-Butyldiphenylsilanyloxy)-9-(tert-butyldiphenylsilanyloxymethyl)-2-methylene-2,3,4,7,8,9-hexahydro-2-oxonineC42H52O3Si2Ee = 100%[α]D25=-30.0 (c 0.43, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (8S,9R)

(2R,5Z,8S,9R)-8-tert-Butyldiphenylsilanyloxy)-9-(tert-butyldiphenylsilanyloxymethyl)-2-phenylselanylmethyl-2,3,4,7,8,9-hexahydrooxonine-2-carbaldehydeC48H58O3SeSi2Ee = 100%[α]D25=+14.6 (c 0.43, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2S,5Z,8S,9R)-8-tert-Butyldiphenylsilanyloxy)-9-(tert-butyldiphenylsilanyloxymethyl)-2-phenylselanylmethyl-2,3,4,7,8,9-hexahydrooxonineC48H58O3SeSi2Ee = 100%[α]D21=+0.5 (c 0.89, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2S,8S,9R)

(2R,5Z,8S,9R)-8-tert-Butyldiphenylsilanyloxy)-9-(tert-butyldiphenylsilanyloxymethyl)-2,3,4,7,8,9-hexahydrooxonine-2-carbaldehydeC42H52O4Si2Ee = 100%[α]D25=+62.7 (c 1.21, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2R,5Z,8S,9R)-8-(tert-Butyldiphenylsilanyloxy)-9-(tert-butyldiphenylsilanyloxymethyl)-2-vinyl-2,3,4,7,8,9-hexahydrooxonineC43H54O3Si2Ee = 100%[α]D25=+19.5 (c 0.95, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2R,5Z,8S,9R)-8-(tert-Butyldiphenylsilanyloxy)-9-hydroxymethyl-2-vinyl-2,3,4,7,8,9-hexahydrooxonineC27H36O3SiEe = 100%[α]D25=+48.8 (c 1.135, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2R,5Z,8S,9S)-8-(tert-Butyldiphenylsilanyloxy)-2-vinyl-2,3,4,7,8,9-hexahydrooxonine-9-carbaldehydeC27H34O3SiEe = 100%[α]D25=+30.3 (c 0.37, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9S)

(2R,5Z,8S,9R)-8-(tert-Butyldiphenylsilanyloxy)-2,9-divinyl-2,3,4,7,8,9-hexahydrooxonineC28H36O2SiEe = 100%[α]D25=+66.5 (c 1.8, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(1R,2S,4Z,8R,9Z)-2-tert-(Butyldiphenylsilanyloxy)-11-oxabicyclo[6.2.1]-undeca-4,9-dieneC26H32O2SiEe = 100%[α]D22=+18.0 (c 0.51, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1R,2S,8R)

[(1S,2R)-(tert-Butyldiphenylsilanyloxy)-2-[(R)-cyclopent-2-enyloxy]-1-cyclopent-3-eneC26H32O2SiEe = 100%[α]D22=-6.0 (c 0.52, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1S,2R,R)

(1R,3S,4R,6R,9S)-3-(tert-Butyldiphenylsilanyloxy)-4-hydroxymethyl-6-vinyl-5,10-dioxabicyclo[7.1.0]-decaneC27H36O4SiEe = 100%[α]D25=+56 (c 0.3, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1R,3S,4R,6R,9S)

(1S,3S,4R,6R,9R)-3-(tert-Butyldiphenylsilanyloxy)-4-hydroxymethyl-6-vinyl-5,10-dioxabicyclo[7.1.0]-decaneC27H36O4SiEe = 100%[α]D25=+27.3 (c 0.52, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1S,3S,4R,6R,9R)

(1S,3S,4R,6R,9R)-3-(tert-Butyldiphenylsilanyloxy)-4-hydroxymethyl-6-vinyl-5,10-dioxabicyclo[7.1.0]-decane-4-carbaldehydeC27H34O4SiEe = 100%[α]D25=+21.3 (c 0.56, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1S,3S,4R,6R,9R)

(1S,3S,4R,6R,9R)-3-(tert-Butyldiphenylsilanyloxy)-4,6-divinyl-5,10-dioxabicyclo-[7.1.0]-decaneC28H36O3SiEe = 100%[α]D25=+21.6 (c 0.31, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1S,3S,4R,6R,9R)

(1R,2S,4S,6R,9R,10Z)-2-(tert-Butyldiphenylsilanyloxy)-(5,12-dioxatricyclo-[7.2.1.04,6]dodecaneC26H32O3SiEe = 100%[α]D25=-37 (c 0.2, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1R,2S,4S,6R,9R)

(1R,2S,8R,Z)-2-Hydroxy-11-oxabicyclo[6.2.1]-undeca-4,9-dieneC10H14O2Ee = 100%[α]D25=-1.0 (c 0.42, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1R,2S,8R)

(1R,2S,4Z,8R,9Z)-2-(N(τ)-Methyl urocanic acid)-11-oxabicyclo[6.2.1]undeca-4,9-dien-2-yl esterC17H20N2O3Ee = 100%[α]D25=+36.5 (c 0.2, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1R,2S,8R)

(5Z,8S,9R)-8-Benzyloxy-9-(tert-butyldiphenylsilanyloxymethyl)-2-methylene-2,3,4,7,8,9-hexahydrooxonineC33H40O3SiEe = 100%[α]D20=-22.6 (c 1.75, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (8S,9R)

(2R,5Z,8S,9R)-8-Benzyloxy-9-(tert-butyldiphenylsilanyloxy-methyl)-2-methoxy-2-phenylselanylmethyl-2,3,4,7,8,9-hexahydrooxonineC40H48O4SeSiEe = 100%[α]D25=+63.3 (c 0.35, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2R,5Z,8S,9R)-8-Benzyloxy-9-(tert-butyldiphenylsilanyloxymethyl)-2-methoxy-2,3,4,7,8,9-hexahydrooxonine-2-carbaldehydeC34H42O5SiEe = 100%[α]D25=+63.3 (c 1.26, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2R,5Z,8S,9R)-8-Benzyloxy-9-(tert-butyldiphenylsilanyloxymethyl)-2-methoxy-2-vinyl-2,3,4,7,8,9-hexahydrooxonineC35H44O4SiEe = 100%[α]D25=+110.4 (c 0.58, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2R,5Z,8S,9R)-8-Benzyloxy-9-hydroxymethyl-2-methoxy-2-vinyl-2,3,4,7,8,9-hexahydrooxonineC19H26O4Ee = 100%[α]D25=+224 (c 0.36, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2R,5Z,8S,9R)-8-Benzyloxy-2-methoxy-2,9-divinyl-2,3,4,7,8,9-hexahydrooxonineC20H26O3Ee = 100%[α]D25=+231.5 (c 0.4, CHCl3)Source of chirality: synthesis from 2-deoxy-d--d-riboseAbsolute configuration: (2R,8S,9R)

(2R,8S,9R,5Z)-2-Methoxy-2-hydroxymethyl-8-benzyloxy-9-(tert-butyldiphenylsilanyloxymethyl)-2,3,4,7,8,9-hexahydrooxonineC34H44O5SiEe = 100%[α]D25=+5.5 (c 0.13, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2R,8S,9R,5Z)-2-Methoxy-2,9-dihydroxymethyl-8-benzyloxy-2,3,4,7,8,9-hexahydrooxonineC18H26O5Ee = 100%[α]D25=+162.1 (c 0.68, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(1S,3S,4R,6R,9R)-3-Benzyloxy-6-methoxy-4,6-divinyl-5,10-dioxabicyclo[7.1.0]decaneC20H26O4Ee = 100%[α]D25=+129.4 (c 0.48, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1S,3S,4R,6R,9R)

(2R,8S,9R)-8-Benzyloxy-9-(tert-butyldiphenylsilanyloxymethyl)-2-methoxy-2,3,4,5,6,7,8,9-octahydrooxonine-2-carbaldehydeC34H34O5SiEe = 100%[α]D25=+15.5 (c 0.85, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2R,8S,9R)-8-Benzyloxy-9-(tert-butyldiphenylsilanyloxymethyl)-2-methoxy-2-vinyl-2,3,4,5,6,7,8,9-octahydrooxonineC35H46O4SiEe = 100%[α]D25=+35.2 (c 1.9, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2R,8S,9R)-8-Benzyloxy-9-hydroxymethyl-2-methoxy-2-vinyl-2,3,4,5,6,7,8,9-octahydrooxonineC19H28O4Ee = 100%[α]D25=+95.4 (c 0.89, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2R,8S,9R)-8-Benzyloxy-2-methoxy-2,9-divinyl-2,3,4,5,6,7,8,9-octahydrooxonineC20H28O3Ee = 100%[α]D23=+32.6 (c 0.39, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2R,5Z,8S,9R)-8-(tert-Butyldiphenylsilanyloxy)-9-(tert-butyl-diphenylsilanyloxymethyl)-2-methoxy-2-phenylselanylmethyl-2,3,4,7,8,9-hexahydrooxonineC49H60O4SeSi2Ee = 100%[α]D22=+68.2 (c 0.20, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2R,5Z,8S,9R)-8-(tert-Butyldiphenylsilanyloxy)-9-(tert-butyldiphenylsilanyloxymethyl)-2-methoxy-2,3,4,7,8,9-hexahydrooxonine-2-carbaldehydeC43H54O5Si2Ee = 100%[α]D22=+66.7 (c 0.6, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2S,5Z,8S,9R)-8-(tert-Butyldiphenylsilanyloxy)-9-(tert-butyldiphenylsilanyloxymethyl)-2-methoxy-2,3,4,7,8,9-hexahydrooxonine-2-carbaldehydeC43H54O5Si2Ee = 100%[α]D22=+40.8 (c 0.73, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2S,8S,9R)

(2R,5Z,8S,9R)-8-(tert-Butyldiphenylsilanyloxy)-9-(tert-butyldiphenylsilanyloxymethyl)-2-methoxy-2-vinyl-2,3,4,7,8,9-hexahydrooxonineC44H56O4Si2Ee = 100%[α]D25=+89.5 (c 1.0, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(5Z,8S,9R)-8-(tert-Butyldiphenylsilanyloxy)-2-methylene-9-vinyl-2,3,4,7,8,9-hexahydrooxonineC27H34O2SiEe = 100%[α]D25=-50.0 (c 0.47, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (8S,9R)

(2R,5Z,8S,9R)-8-(tert-Butyldiphenylsilanyloxy)-2,9-divinyl-2-methoxy-2,3,4,7,8,9-hexahydrooxonineC29H38O3SiEe = 100%[α]D25=+197.8 (c 0.64, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2R,8S,9R,5Z)-2-Methoxy-2-[(Z)-prop-1-enyl]-8-(tert-butyldiphenylsilanyloxy)-9-vinyl-2,3,4,7,8,9-hexahydrooxonineC30H40O3SiEe = 100%[α]D25=+143.4 (c 0.37, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(2R,8S,9R,5Z)-2-Methoxy-2-[(Z)-prop-1-enyl]-9-vinyl-2,3,4,7,8,9-hexahydrooxonin-3-olC14H22O3Ee = 100%[α]D25=+121.8 (c 0.45, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,8S,9R)

(1S,3S,4R,6R,9R)-3-(tert-Butyldiphenylsilanyloxy)-4,6-divinyl-6-methoxy-5,10-dioxa-bicyclo[7.1.0]-decaneC29H38O4SiEe = 100%[α]D25=+89 (c 0.3, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1S,3S,4R,6R,9R)

(1R,2Z,5S)-5-(tert-Butyldiphenylsilanyloxy)-cyclopent-2-en-1-olC21H26O2SiEe = 100%[α]D25=+198 (c 0.64, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1R,5S)

(3S,8S,9R,5Z)-3-Hydroxy-8-(tert-butyldiphenylsilanyloxy)-9-vinyl-2,3,4,7,8,9-hexahydrooxonin-2(7H)-oneC26H32O4SiEe = 100%[α]D25=+27.4 (c 0.12, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (3S,8S,9R)

(3S,8S,9R,5Z)-3-Trimethylsilanyloxy-8-(tert-butyldiphenylsilanyloxy)-9-vinyl-2,3,4,7,8,9-hexahydrooxonin-2(7H)-oneC29H40O4Si2Ee = 100%[α]D25=+33.7 (c 0.27, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (3S,8S,9R)

(3S,8S,9R,5Z)-2-Methylene-3-trimethylsilanyloxy-8-(tert-butyldiphenylsilanyloxy)-9-vinyl-2,3,4,7,8,9-hexahydrooxonineC30H42O3Si2Ee = 100%[α]D25=+10.9 (c 0.32, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (3S,8S,9R)

(3S,8S,9R,5Z)-2-Methylene-3-hydroxy-8-(tert-butyldiphenylsilanyloxy)-9-vinyl-2,3,4,7,8,9-hexahydrooxonineC27H34O3SiEe = 100%[α]D25=+17.0 (c 0.10, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (3S,8S,9R)

(3S,8S,9R,5Z)-2-Methylene-3-dimethylsilanyloxy-8-(tert-butyldiphenylsilanyloxy)-9-vinyl-2,3,4,7,8,9-hexahydrooxonineC29H40O3Si2Ee = 100%[α]D25=+16.8 (c 0.22, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (3S,8S,9R)

(2R,3S,8S,9R,5Z)-2-Hydroxymethyl-3-hydroxy-8-(tert-butyldiphenylsilanyloxy)-9-vinyl-2,3,4,7,8,9-hexahydrooxonineC27H36O4SiEe = 100%[α]D25=+27.3 (c 0.17, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,3S,8S,9R)

(2S,3S,8S,9R,5Z)-2-Hydroxymethyl-3-hydroxy-8-(tert-butyldiphenylsilanyloxy)-9-vinyl-2,3,4,7,8,9-hexahydrooxonineC27H36O4SiEe = 100%[α]D24=+63.6 (c 0.06, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2S,3S,8S,9R)

(2R,4aR,6R,7S,11aS,Z)-7-tert-Butyldiphenylsilyloxy-2-(4-methoxyphenyl)-6-vinyl-4a,6,7,8,11,11a-hexahydro-4H-[1,3]dioxino[5,4-b]oxonineC35H42O5SiEe = 100%[α]D24=+36.3 (c 0.34, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,4aR,6R,7S,11aS)

(2R,4aS,6R,7S,11aS,Z)-7-tert-Butyldiphenylsilyloxy -2-(4-methoxyphenyl)-6-vinyl-4a,6,7,8,11,11a-hexahydro-4H-[1,3]dioxino[5,4-b]oxonineC35H42O5SiEe = 100%[α]D24=+115.6 (c 0.30, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,4aS,6R,7S,11aS)

(2S,3S,8S,9R,5Z)-2-Hydroxymethyl-3-(4-methoxybenzyloxy)-8-(tert-butyldiphenylsilanyloxy)-9-vinyl-2,3,4,7,8,9-hexahydrooxonineC35H44O5SiEe = 100%[α]D24=+88.2 (c 0.38, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2S,3S,8S,9R)

(2R,3S,8S,9R,5Z)-3-(4-Methoxybenzyloxy)-8-(tert-butyldiphenylsilanyloxy)-9-vinyl-2,3,4,7,8,9-hexahydrooxonin-2-carbaldehydeC35H42O5SiEe = 100%[α]D24=+19.2 (c 0.18, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,3S,8S,9R)

(2S,3S,8S,9R,5Z)-3-(4-Methoxybenzyloxy)-8-(tert-butyldiphenylsilanyloxy)-2,9-divinyl-2,3,4,7,8,9-hexahydrooxonineC36H44O4SiEe = 100%[α]D24=+70.7 (c 0.60, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2S,3S,8S,9R)

(1R,2S,7S,8R,4Z,9Z)-7-(4-Methoxybenzyloxy)-11-oxa-bicyclo[6.2.1]undeca-4,9-dien-2-olC18H22O4Ee = 100%[α]D24=-27.8 (c 0.11, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1R,2S,7S,8R)

(1S,2R)-2-((1S,5S)-5-(4-methoxybenzyloxy)cyclopent-2-enyloxy)cyclopent-3-enolC18H22O4Ee = 100%[α]D24=+25.7 (c 0.14, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1S,2R,1′S,5′S)

(1S,2S,7S,8R,4Z,9Z)-2-Hydroxy-7-(tert-butyldiphenylsilanyloxy)-11-oxa-bicyclo[6.2.1]undeca-4,9-dieneC26H32O3SiEe = 100%[α]D24=+7.2 (c 0.19, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1S,2S,7S,8R)

(1S,7S,8R,4Z,9Z)-7-(tert-Butyldiphenylsilanyloxy)-11-oxabicyclo[6.2.1]undeca-4,9-dien-2-oneC26H30O3SiEe = 100%[α]D24=+126.4 (c 0.22, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1S,7S,8R)

(1R,7S,8S,4Z,9Z)-7-(4-Methoxybenzyloxy)-11-oxa-bicyclo[6.2.1]undeca-4,9-dien-2-oneC18H20O4Ee = 100%[α]D24=+82.7 (c 0.15, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1R,7S,8S)

(2R,3S,8S,9R,5Z)-2-Hydroxymethyl-8-(tert-butyldiphenylsilanyloxy)-3-(4-methoxybenzyloxy)-9-vinyl-2,3,4,7,8,9-hexahydrooxonineC35H44O5SiEe = 100%[α]D24=+71.0 (c 0.46, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,3S,8S,9R)

(2S,3S,8S,9R,5Z)-3-(4-Methoxybenzyloxy)-8-(tert-butyldiphenylsilanyloxy)-9-vinyl-2,3,4,7,8,9-hexahydrooxonin-2-carbaldehydeC35H42O5SiEe = 100%[α]D24=+21.6 (c 0.49, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2S,3S,8S,9R)

(2R,3S,8S,9R,5Z)-3-(4-Methoxybenzyloxy)-8-(tert-butyldiphenylsilanyloxy)-2,9-divinyl-2,3,4,7,8,9-hexahydrooxonineC36H44O4SiEe = 100%[α]D24=+36.6 (c 0.25, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,3S,8S,9R)

(2R,3S,8S,9R,5Z)-3-Hydroxy-8-(tert-butyldiphenylsilanyloxy)-2,9-divinyl-2,3,4,7,8,9-hexahydrooxonineC28H36O3SiEe = 100%[α]D24=+30.1 (c 0.17, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,3S,8S,9R)

(2R,3S,8S,9R,5Z)-2,9-Divinyl-2,3,4,7,8,9-hexahydrooxonine-3,8-diolC12H18O3Ee = 100%[α]D24=+155.0 (c 0.20, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,3S,8S,9R)

((1S,2R)-3-tert-Butyldiphenylsilanyloxy-2-((1R,5S)-5-(4-methoxybenzyloxy)cyclopent-2-enyloxy)cyclopent-3-eneC34H40O4SiEe = 100%[α]D24=+76.7 (c 0.06, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1S,2R,1′R,5′S)

(2R,3S,5Z,8Z)-3-(tert-Butyldiphenylsilanyloxy)-9-[(Z)-prop-1-enyl]-2-vinyl-2,3,4,7-tetrahydrooxonineC29H36O2SiEe = 100%[α]D24=+36.6 (c 0.25, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (2R,3S)

(1R,2S,4Z,6Z,9Z)-2-(tert-Butyldiphenylsilanyloxy)-11-oxa-bicyclo[4.4.1]undeca-4,6,9-trieneC26H30O2SiEe = 100%[α]D24=+17.0 (c 0.27, CHCl3)Source of chirality: synthesis from 2-deoxy-d-riboseAbsolute configuration: (1R,2S)