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S1 SUPPORTING INFORMATION FIRST STEREOSELECTIVE SYNTHESIS OF (-)-SIPHONODIOL AND (-)-TETRAHYDROSIPHONODIOL, BIOACTIVE POLYACETYLENES FROM MARINE SPONGES Susana López,* Francisco Fernández-Trillo, Pilar Midón, Luis Castedo, and Carlos Saá Departamento de Química Orgánica, Facultade de Química, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, SPAIN qosuslop@usc.es Table of Contents. General Methods...S1 Experimental Procedures for Significant Intermediates...S2-S7 NMR Spectra of All Compounds...S8-S35 General methods. Solvents were dried according to published methods and distilled before use. 34 All other reagents were commercial compounds of the highest purity available. Reactions were carried out under atmosphere of argon in flame-dried glassware with magnetic stirring. Chemical shifts (δ) are expressed in parts per million (ppm) relative to tetramethylsilane as internal reference. 13 C multiplicities were assigned with the aid of the DEPT pulse sequence. Optical rotations were measured at 20 C and at the concentrations (c)(g/100 ml) indicated; the measurements were carried out in a cell with a path length of 0.5 dm. 34 Armarego, W. L. F.; Perrin, D. D. Purification of Laboratory Chemicals, 4 th Ed; Butterworth- Heinemann: Oxford, 1996.

S2 Experimental Procedures. Hexane-1,6-dial (5). To a vigorously stirred suspension of chromatographic grade silica gel (105 g, 1.75 mol) in CH 2 Cl 2 (500 ml) was added dropwise an aqueous solution of NaIO 4 (0.65 M, 105 ml, 68.2 mmol) whence a flaky suspension was formed. A solution of trans-cyclohexane-1,2-diol (3) (6.08 g, 52.3 mmol) in CH 2 Cl 2 (200 ml) was then added, and the reaction was stirred for 24 h. The mixture was filtered on a sintered glass, and the silica gel was thoroughly washed with CH 2 Cl 2. Evaporation of the solvent afforded the title compound (5.91 g, quantitative) as a colorless oil. 35 No further purification was necessary. 1 H-NMR (250 MHz, CDCl 3 ) δ 1.65 (4H, t, J = 6.9 Hz), 2.45 (4H, dt, J = 1.4, 6.9 Hz), 9.76 (2H, t, J = 1.4 Hz) ppm. 13 C-NMR (75 MHz, CDCl 3 ) δ 21.5 (2xCH 2 ), 43.6 (2xCH 2 ), 201.6 (2xCH) ppm. IR (CsI) ν 1723 (C=O) cm -1. MS (EI) m/z (%) 115 (MH +, 100), 114 (M +, 31), 113 (85), 85 (41), 57 (67). Octane-1,8-dial (6). Following the same procedure described for 5, treatment of chromatographic grade silica gel (24.8 g, 0.41 mol) in CH 2 Cl 2 (120 ml) with an aqueous solution of NaIO 4 (0.65 M, 25 ml, 16.1 mmol), and cis-cyclooctane-1,2-diol (4) (1.79 g, 12.41 mmol) in CH 2 Cl 2 (50 ml) afforded the title compound (1.76 g, quantitative) as a colorless oil. 35b 1 H-NMR (250 MHz, CDCl 3 ) δ 1.3-1.4 (4H, m), 1.6-1.7 (4H, m), 2.43 (4H, dt, J = 1.3, 7.3 Hz), 9.76 (2H, t, J = 1.3 Hz) ppm. 13 C-NMR (75 MHz, CDCl 3 ) δ 21.8 (2xCH 2 ), 28.8 (2xCH 2 ), 43.7 (2xCH 2 ), 202.5 (2xCH) ppm. IR (CsI) ν 1723 (C=O) cm -1. MS (CI) m/z (%) 143 (MH +, 8), 142 (M +, 9), 141 (93), 125 (51), 95 (100), 81 (86). HRMS (EI) calcd for C 8 H 14 O 2 142.0994, found 142.0988. 1,1,8,8,-Tetrabromoocta-1,7-diene (7). To a solution of Ph 3 P (12.0 g, 45.6 mmol) in CH 2 Cl 2 (34 ml), cooled in an ice-water bath, was slowly added CBr 4 (7.56 g, 22.8 mmol) in CH 2 Cl 2 (15 ml) at a rate to maintain the reaction temperature below 15 C. A solution of hexane-1,6-dial (5) (1.0 g, 8.76 mmol) and Et 3 N (2.50 ml, 1.80 g, 18.08 mmol) in CH 2 Cl 2 (10 ml) was added dropwise at 0 C. After stirring for 35 min at this temperature, the reaction was warmed to rt for 1 h. The mixture was poured into hexane (100 ml) and filtered through Celite. The solid was washed with hexane (3 x 20 ml) and the filtrate was concentrated under reduced pressure. Hexane was added (20 ml) and the mixture was filtered again. The filtrate was concentrated and purified by column chromatography (hexane) to give the title 35 (a) Gupta, D. N.; Hodge, P.; Davies, J. E. J. Chem. Soc., Perkin Trans. 1 1981, 2970-2973. (b) Daumas, M.; Vo-Quang, Y.; Vo-Quang, L.; Legoffic, F. Synthesis 1989, 64-65.

S3 compound as a colorless oil (3.03 g, 81% yield). 1 H-NMR (250 MHz, CDCl 3 ) δ 1.4-1.5 (4H, m), 2.1-2.3 (4H, m), 6.38 (2H, t, J = 7.4 Hz) ppm. 13 C-NMR (63 MHz, CDCl 3 ) δ 27.1 (2xCH 2 ), 32.6 (2xCH 2 ), 89.1 (2xC), 138.2 (2xCH) ppm. MS (CI) m/z (%) 430 (1), 428 (3), 426 (4), 424 (3), 422 (M +, 1), 349 (3), 347 (11), 345 (13), 343 (6), 267 (34), 265 (66), 263 (36), 201 (39), 199 (80), 187 (24), 185 (100), 183 (79). HRMS (CI) calcd for C 8 H 10 Br 4 421.7516, found 421.7512. 1,1,10,10-Tetrabromodeca-1,9-diene (8). Following the same procedure described for 7, reaction of Ph 3 P (13.8 g, 52.7 mmol), CBr 4 (8.7 g, 26.3 mmol), octane-1,8-dial (6) (1.44 g, 10.13 mmol) and Et 3 N (2.8 ml, 2.05 g, 20.26 mmol) in CH 2 Cl 2 (50 ml) afforded, after purification by flash chromatography (hexane), the title compound as a colorless oil (4.29 g, 93% yield). 1 H-NMR (250 MHz, CDCl 3 ) δ 1.3-1.5 (8H, m), 2.0-2.1 (4H, m), 6.38 (2H, t, J = 7.3 Hz) ppm. 13 C-NMR (75 MHz, CDCl 3 ) δ 27.7 (2xCH 2 ), 28.8 (2xCH 2 ), 33.0 (2xCH 2 ), 88.6 (2xC), 138.6 (2xCH) ppm. MS (CI) m/z (%) 458 (2), 456 (7), 454 (11), 452 (8), 450 (M +, 2), 377 (1), 375 (3), 371 (2), 213 (49), 211 (46), 210 (32), 199 (73), 197 (43), 132 (74), 131 (100), 81 (70). HRMS (CI) calcd for C 10 H 14 Br 4 449.7829, found 449.7828. (1Z,7Z)-1,8-Dibromoocta-1,7-diene (9). A mixture of PPh 3 (0.19 g, 0.72 mmol) and Pd(OAc) 2 (0.04 g, 0.18 mmol) in dry CH 2 Cl 2 (30 ml) was stirred at rt for 15 min to generate a light, yellow solution. A solution of 1,1,8,8-tetrabromoocta-1,7-diene (7) (0.95 g, 2.23 mmol) in CH 2 Cl 2 (5 ml) and n-bu 3 SnH (2.2 ml, 2.42 g, 8.31 mmol) were added sequentially, and the mixture was stirred for 2 h at rt. After the reaction was completed, it was diluted with hexane (60 ml) and washed with water (3 x 50 ml) and brine (3 x 50 ml). The ethereal extract was dried over Na 2 SO 4 and the solvent removed under reduced pressure. The residue was purified by column chromatography (hexane) to give the title compound as a colorless oil (0.48 g, 81% yield). 1 H-NMR (300 Hz, C 6 D 6 ) δ 1.0-1.1 (4H, m), 2.0-2.1 (4H, m), 5.57 (2H, c, J = 6.9 Hz), 5.82 (2H, d, J = 6.9 Hz) ppm. 13 C-NMR (75 MHz, CDCl 3 ) δ 27.4 (2xCH 2 ), 29.3 (2xCH 2 ), 107.8 (2xCH), 134.4 (2xCH) ppm. MS (CI) m/z (%) 267 (6), 265 (12), 263 (M +, 6), 201 (50), 199 (100), 197 (52). HRMS (CI) calcd for C 8 H 12 Br 2 266.8276, found 266.8268. (1Z,9Z)-1,10-Dibromodeca-1,9-diene (10). Following the procedure described above, treatment of PPh 3 (0.21 g, 0.80 mmol) and Pd(OAc) 2 (0.04 g, 0.20 mmol) in dry CH 2 Cl 2 (30 ml) with a solution of 1,1,10,10-tetrabromodeca-1,9-diene (8) (1.13 g, 2.49 mmol) in CH 2 Cl 2 (.5 ml) and n-bu 3 SnH (2.4 ml, 2.70 g, 9.21 mmol) afforded, after purification by flash chromatography (hexane), the title compound as a colorless oil (0.57 g, 78% yield). 1 H-NMR (250 Hz, C 6 D 6 ) δ 1.0-1.2 (8H, m), 2.0-2.1 (4H, m), 5.64 (2H, c, J = 7.0 Hz), 5.85 (2H, dt, J = 7.0, 1.4 Hz) ppm. 13 C-NMR (75 MHz, CDCl 3 ) δ 28.0 (2xCH 2 ), 28.8 (2xCH 2 ), 29.6 (2xCH 2 ), 107.6 (2xCH), 134.9 (2xCH) ppm. MS (CI) m/z (%) 298 (<1), 295 (1.5), 294 (M +, <1), 95 (100), 81 (100), 67 (92). HRMS (CI) calcd for C 10 H 16 Br 2 293.9619, found 293.9618.

S4 5,6-O-Cyclohexylidene-L-gulono-1,4-lactone (17). To a suspension of L-gulono-1,4-lactone (16) (3.26 g, 18.30 mmol) and camphorsulfonic acid (0.07 g, 0.30 mmol) in dry DMF (16 ml) was added cyclohexanone dimethylketal (4.40 ml, 4.18 g, 29.00 mmol) and the mixture was allowed to react for 3 days. Et 3 N (1 ml) was then added and the resulting solution was concentrated in vacuum (60 C). Dilution in toluene (15 ml) and cooling at 4 C afforded a solid that was filtered, dissolved in Me and recrystallized at -20 C, to give the title compound as a white solid (3.90 g, 83% yield). [α] D : + 44.2 (c 1.06, CHCl 3 ) mp: 170-172 C (CH 2 Cl 2 ). 1 H-NMR (500 MHz, DMSO-d 6 ) δ 1.4-1.5 (2H, m), 1.5-1.6 (8H, m), 3.7-3.8 (1H, m), 4.0-4.1 (1H, m), 4.2-4.3 (3H, m), 4.42 (1H, dd, J = 4.7, 7.4 Hz), 5.33 (1H, d, J = 4.3 Hz), 5.78 (1H, d, J = 7.4 Hz) ppm. 13 C-NMR (63 MHz, DMSO-d 6 ) δ 23.4 (CH 2 ), 23.5 (CH 2 ), 24.6 (CH 2 ), 34.4 (CH 2 ), 37.0 (CH 2 ), 64.0 (CH 2 ), 69.1 (CH), 70.2 (CH), 74.7 (CH), 81.3 (CH), 109.4 (C), 176.0 (C) ppm. IR (CsI) ν 3448 (O H), 1780 (COOR) cm -1. MS (EI) m/z (%) 258 (M +, 9), 229 (14), 215 (71), 141 (6), 83 (31), 55 (100). Elemental analysis: calcd for C 12 H 18 O 6 : C, 55.81; H, 7.02; found: C, 55.81; H, 7.31. 2,3-O-Cyclohexylidene-L-glyceraldehyde (18). To a well stirred suspension of KIO 4 (13.87 g, 60.30 mmol) and KHCO 3 (6.04 g, 60.39 mmol) in H 2 O (36 ml) was slowly added, over 15 min, a solution of 5,6-O-cyclohexylidene-L-gulono-1,4-lactone (17) (7.42 g, 28.73 mmol) in dry THF (36 ml) and the mixture was allowed to react for 8 h at rt. After cooling in an ice/water bath, the mixture was filtrated over Celite and washed thoroughly with ethyl acetate. The organic phase was extracted with ethyl acetate (2 x 50 ml), dried over Na 2 SO 4 (anh) and concentrated to give the title compound as a colorless oil (4.50 g, 92% yield). [α] D : - 58.0 (c 3.4, CHCl 3 ) [enantiomer: 18 + 61.2 (c 3.4, benzene)]. bp: 58-60 C, 1.0 mmhg. 1 H-NMR (500 MHz, CDCl 3 ) δ 1.3-1.4 (2H, m), 1.5-1.7 (8H, m), 4.0-4.2 (2H, m), 4.3-4.4 (1H, m), 9.71 (1H, d, J = 1.7 Hz) ppm. 13 C-NMR (63 MHz, CDCl 3 ) δ 23.7 (CH 2 ), 23.8 (CH 2 ), 24.9 (CH 2 ), 34.6 (CH 2 ), 35.8 (CH 2 ), 65.2 (CH 2 ), 79.5 (CH), 111.9 (C), 202.1 (C) ppm. IR (CsI) ν 1736 (C=O) cm -1. MS (CI) m/z (%) 171 (MH +, 100), 141 (37), 127 (31), 29 (55). HRMS (EI) calcd for C 9 H 14 O 3 170.0943, found 170.0940. (R)-1,2-O-Cyclohexylidenedioxy-4,4-diiodobut-3-ene (19). To a solution of CHI 3 (7.52 g, 19.10 mmol) in dry THF (64 ml) was added, sequentially, PPh 3 (5.48 g, 20.89 mmol) and t-buok (2.57 g, 22.90 mmol) and the mixture was allowed to react for 15 min before cooling in an ice/water bath. A solution of 2,3-O-cyclohexylidene-L-glyceraldehyde (18) (2.60 g, 15.28 mmol) in dry THF (12 ml) was then added and the mixture was allowed to react at 0 C for 4.5 h. Saturated aqueous solution of NaCl (75 ml) was added and the mixture was extracted with ether (3 x 100 ml). The ethereal fractions were washed with brine (2 x 300 ml), dried over anhydrous Na 2 SO 4 and concentrated. Purification by

S5 flash chromatography (hexane/ethyl acetate: 90:10) afforded the title compound as a colorless oil (5.42 g, 84% yield). [α] D : + 4.20 (c 1.41, CHCl 3 ). 1 H-NMR (250 MHz, CDCl 3 ) δ 1.3-1.4 (2H, m), 1.5-1.6 (8H, m), 3.66 (1H, dd, J = 8.4, 6.6 Hz), 4.18 (1H, dd, J = 8.4, 6.3 Hz), 4.4-4.5 (1H, m), 7.15 (1H, d, J = 7.3 Hz) ppm. 13 C-NMR (100 MHz, CDCl 3 ) δ 13.4 (C), 23.8 (CH 2 ), 23.9 (CH 2 ), 25.0 (CH 2 ), 35.1 (CH 2 ), 36.1 (CH 2 ), 67.0 (CH 2 ), 81.1 (CH), 110.6 (C), 150.9 (CH) ppm. MS (CI) m/z (%) 421 (MH +, 3), 420 (M +, 1), 141 (27), 99 (100), 81 (15). Elemental analysis: calcd for C 10 H 14 O 2 I 2 : C, 28.60; H, 3.36; found: C, 28.77; H, 3.39. (R)-1,2-O-Cyclohexylidenedioxy-4-iodobut-3-yne (20). To a solution of (R)-1,2-O-cyclohexylidene dioxy-4,4-diiodobut-3-ene (19) (1.07 g, 2.55 mmol) in dry THF (25 ml), cooled in an ice/water bath, was added n-bu 4 NF (1.0 M solution in THF, 7.70 ml, 7.70 mmol) and the mixture was allowed to react at rt for 27 h. The mixture was diluted with ether (50 ml), washed with brine (3 x 70 ml), dried over anhydrous Na 2 SO 4 and concentrated. Purification by flash chromatography (hexane/ethyl acetate 90:10) afforded the title compound as a colorless oil (0.71 g, 95% yield). [α] D : - 36.6 (c 0.31, CHCl 3 ). [bibliographic: 22-37.5 (c 1.08, CHCl 3 )]. 1 H-NMR (250 MHz, CDCl 3 ) δ 1.2-1.4 (2H, m), 1.5-1.7 (6H, m), 1.7-1.8 (2H, m), 3.92 (1H, dd, J = 8.0, 6.1 Hz), 4.13 (1H, dd, J = 8.0, 6.4 Hz), 4.82 (H, dd, J = 6.4, 6.1 Hz) ppm. 13 C-NMR (75 MHz, CDCl 3 ) δ 3.5 (C), 23.9 (2xCH 2 ), 25.0 (CH 2 ), 35.4 (CH 2 ), 35.7 (CH 2 ), 66.4 (CH), 69.5 (CH 2 ), 92.0 (C), 111.1 (C) ppm. IR (CsI) ν 2185 (C C) cm -1. MS (CI) m/z (%) 293 (MH +, 95), 292 (M +, 83), 291 (30), 249 (100), 165 (8), 141 (57), 99 (22). HRMS (CI) calcd for C 10 H 14 O 2 I 293.0039, found 293.0031. (R)-4-Iodobut-3-yne-1,2-diol (21). To a solution of (R)-1,2-O-cyclohexylidenedioxy-4-iodobut-3-yne (20) (2.62 g, 8.97 mmol) in dry Me (150 ml) was added Dowex 50WX8 resin (16.51 g) and the mixture was allowed to react for 3 days. The suspensión was filtered through Celite and washed thoroughly with Me (10 ml). The methanolic extract was washed with hexane (5 x 70 ml) and concentrated. Purification by flash chromatography (CH 2 Cl 2 /ethyl acetate 50:50) afforded the title compound as a white solid (1.78 g, 94% yield). [α] D : -5.11 (c 0.47, Et). 1 H-NMR (300 MHz, CD 3 OD) δ 3.5-3.6 (2H, m), 4.3-4.4 (1H, m) ppm. 13 C-NMR (75 MHz, CD 3 OD) δ 6.1 (C), 65.5 (CH), 67.4 (CH 2 ), 93.8 (C) ppm. IR (CsI) ν 3334, 3283 (O H), 2185, 2172 (C C) cm -1. MS (CI) m/z (%) 195 (M + -, 5), 181 (7), 161 (62), 68 (100). Elemental analysis: calcd for C 4 H 5 O 2 I: C, 22.66; H, 2.38; found: C, 22.27; H, 2.32. 1-[(3 -Cyanopropyl)dimethylsilyl]hepta-1,6-diyne (23). To a solution of commercial hepta-1,6-diyne (22) (2.00 ml, 1.62 g, 17.58 mmol) in dry THF (17 ml) was added dropwise EtMgBr (1.00 M solution

S6 in THF, 15.20 ml, 15.20 mmol) and the mixture was stirred for 2.5 h. A solution of (3 -cyanopropyl) dimethylsilylchloride (2.21 ml, 2.19 g, 13.54 mmol) in dry THF (3 ml) was then added. After reacting for 12 h, the mixture was diluted with ether (20 ml) and washed with saturated aqueous solutions of NH 4 Cl (40 ml), NaHCO 3 (2 x 40 ml) and NaCl (2 x 40 ml), dried over anhydrous Na 2 SO 4 and concentrated. Purification by flash chromatography (hexane/ethyl acetate 70:30), afforded the title compound as a yellow oil (2.28 g, 77% yield), together with 0.38 g (16%) of 1,7-bis[(3 -cyanopropyl) dimethylsilyl]hepta-1,6-diyne (24). Spectral data for 23: 1 H-NMR (250 MHz, CDCl 3 ) δ 0.14 (6H, s), 0.7-0.8 (2H, m), 1.7-1.8 (4H, m), 1.97 (1H, t, J = 2.6 Hz), 2.3-2.4 (6H, m) ppm. 13 C-NMR (63 MHz, CDCl 3 ) δ -2.0 (2xCH 3 ), 15.5 (CH 2 ), 17.2 (CH 2 ), 18.5 (CH 2 ), 20.1 (CH 2 ), 20.3 (CH 2 ), 27.1 (CH 2 ), 68.8 (CH), 82.9 (C), 83.0 (C), 107.7 (C), 119.4 (C) ppm. IR (CsI) ν 3296 ( C H), 2246 (C N), 2181 (C C) cm -1. MS (EI) m/z (%) 217 (M +, 4), 216 (14), 202 (35), 188 (52), 174 (29), 147 (100), 121 (79). HRMS (EI) calcd for C 13 H 19 NSi 217.1287, found 217.1289. Spectral data for 24: 1 H-NMR (300 MHz, CDCl 3 ) δ 0.17 (12H, s), 0.7-0.8 (4H, m), 1.7-1.8 (6H, m), 2.3-2.4 (8H, m) ppm. 13 C-NMR (75 MHz, CDCl 3 ) δ - 1.7 (4xCH 3 ), 15.5 (2xCH 2 ), 18.9 (2xCH 2 ), 20.3 (2xCH 2 ), 20.5 (2xCH 2 ), 27.4 (CH 2 ), 83.0 (2xC), 107.3 (2xC), 119.5 (2xC) ppm. IR (CsI) ν 2245 (C N), 2173 (C C) cm -1. MS (CI) m/z (%) 343 (MH +, 38), 327 (36), 275 (38), 274 (86), 126 (100). HRMS (CI) calcd for C 19 H 31 N 2 Si 2 343.2026, found 343.2031. 2-Iodo-1-triisopropylsilylacetylene (25). To a solution of triisopropylsilylacetylene (4.00 ml, 3.24 g, 17.77 mmol) in dry THF (20 ml), cooled at -78 C, was added MeLi LiBr (1.5 M solution in ether, 12.00 ml, 18.00 mmol) and the mixture was allowed to react for 1 h at that temperature. A solution of I 2 (5.08 g, 20.00 mmol) in dry THF (30 ml) was then added dropwise. After reacting at rt for 1.5 h, the mixture was diluted with brine (50 ml) and the aqueous layer was extracted with ether (3 x 40 ml). The ethereal fraction was washed with saturated aqueous solution of Na 2 S 2 O 3 (3 x 100 ml), dried over Na 2 SO 4 (anh), and concentrated. Purification by flash chromatography (hexane) afforded the title compound as a colorless oil (5.30 g, 96% yield). 1 H-NMR (250 MHz, CDCl 3 ) δ 1.0-1.1 (21H, m) ppm. 13 C-NMR (75 MHz, CDCl 3 ) δ 11.4 (3xCH), 18.5 (6xCH 3 ), 19.9 (C), 100.8 (C) ppm. General method for assessment of the enantiomeric excess of chiral diols. To a solution of (R)-4- iodobut-3-yne-1,2-diol (21) (0.05 g, 0.24 mmol) in CH 2 Cl 2 (7 ml) was added (R)-methoxyphenylacetic acid (0.08 g, 0.48 mmol), EDC (0.10 g, 0.52 mmol) and DMAP (1% molar) and the mixture was stirred at rt for 14 h. After the reaction was completed, it was diluted with Et 2 O (5 ml) and washed with water (10 ml), HCl 1N (2 x 10 ml) and saturated aqueous NaHCO 3 solution (10 ml). The organic layer was dried over Na 2 SO 4 and the solvent was removed under reduced pressure to yield a colorless oil as a mixture of (R)-1,2-bis[(R)-2-methoxy-2-phenylacetoxy]-4-iodobut-3-yne and (S)-1,2-bis[(R)-2-

S7 methoxy-2-phenylacetoxy]-4-iodobut-3-yne. The integration of the signal corresponding to the Hα to carbonyl group in the auxiliar reagent led to assess the enantiomeric excess which resulted in all cases > 98%.

S8 NMR Spectra. Hexane-1,6-dial (5). O O 5

S9 Octane-1,7-dial (6). O O 6

S10 1,1,8,8-Tetrabromoocta-1,7-diene (7). Br Br 7 Br Br

S11 1,1,10,10-Tetrabromodeca-1,7-diene (8). Br Br 8 Br Br

S12 (1Z,7Z)-1,8-Dibromoocta-1,7-diene (9). Br Br 9

S13 (1Z,9Z)-1,10-Dibromodeca-1,9-diene (10). Br Br 10

S14 (3Z,9Z)-10-Bromo-1-[(3 -cyanopropyl)dimethylsilyl]deca-3,9-dien-1-yne (12). Br CPDMS 12 140 ppm (f1) 130 120 110 100 90 80 70 60 50 40 30 20 10 0

S15 (3Z,9Z)-1,12-Bis-[(3 -cyanopropyl)dimethylsilyl]dodeca-3,9-diene-1,11-diyne (14). CPDMS CPDMS 14

S16 (3Z,11Z)-12-Bromo-1-[(3 -cyanopropyl)dimethylsilyl]dodeca-3,11-dien-1-yne (13). CPDMS Br 13

S17 (3Z,11Z)-1,14-Bis-[(3 -cyanopropyl)dimethylsilyl]tetradeca-3,11-diene-1,13-diyne (15). CPDMS CPDMS 15 8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 150 140 130 120 110 100 90 80 70 60 50 40 30 20 10 0

S18 5,6-O-Cyclohexylidene-L-gulono-1,4-lactone (17). O HO HO O O O 17

S19 2,3-O-Cyclohexylidene-L-glyceraldehyde (18). O H O O 18

S20 (R)-1,2-O-Cyclohexylidenedioxy-4,4-diiodobut-3-ene (19). I I O O 19

S21 (R)-1,2-O-Cyclohexylidenedioxy-4-iodobut-3-yne (20). I O O 20

S22 (R)-4-Iodobut-3-yne-1,2-diol (21). I 21

S23 2-Iodo-1-triisopropylsilylacetylene (25). I TIPS 25

S24 1-[(3 -Cyanopropyl)dimethylsilyl]hepta-1,6-diyne (23). CPDMS 23

S25 1,7-Bis[(3 -cyanopropyl)dimethylsilyl]hepta-1,6-diyne (24). CPDMS 24 CPDMS

S26 (R)-11-[(3 -Cyanopropyl)dimethylsilyl]undeca-3,5,10-triyne-1,2-diol (28). CPDMS 28 8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0

S27 (R)-Undeca-3,5,10-triyne-1,2-diol (29). 29 8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0

S28 9-[(3 -Cyanopropyl)dimethylsilyl]-1-triisopropylsilylnona-1,3,8-triyne (26). CPDMS 26 TIPS

S29 1-Triisopropylsilylnona-1,3,8-triyne (27). 27 TIPS

S30 (R)-13-Triisopropylsilyltrideca-3,5,10,12-tetrayne-1,2-diol (30). TIPS 30

S31 (R)-Trideca-3,5,10,12-tetrayne-1,2-diol (31). 31

S32 (2R,14Z,20Z)-23-[(3 -Cyanopropyl)dimethylsilyl]tricosa-14,20-diene-3,5,10,12,22-pentayne-1,2-diol (32). CPDMS 32

S33 (2R,12Z,20Z)-23-[(3 -Cyanopropyl)dimethylsilyl]tricosa-12,20-diene-3,5,10,22-tetrayne-1,2-diol (33). CPDMS 33 8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0

S34 (-)-Siphonodiol (1).

S35 (-)-Tetrahydrosiphonodiol (2).