bryostatins, 50
endo conjugate addition approach, 48
leucascandrolide A, 48
phorboxazole A, 51, 52
(+)-SCH 351448, 48, 49
spongistatin 1, 50, 51
stereochemical consequences, 46, 47
nucleophilic substitution cyclizations
epoxide opening, 59–61
leucascandrolide A, 53
mechanistic considerations, 52, 53
phorboxazoles, 54, 55
spongistatin 1, 53, 54
One-pot reaction, 24, 25
Organocatalytic aldol-Michael reactions, 7
Osmium-catalyzed cyclizations
aminohydroxylation strategy, 24
(+)-cis-solamin, 23, 24
(Z,Z)-diene cyclizations, 25, 26
OsO 4 , 23
7-Oxabicyclo[2.2.1]heptane
cantharidin and analogues, 144–145
with carotenoids, 158–159
Diels–Alder approaches, 161–166
diterpenoid, 150–153
monoterpenoid, 145–147
non-Diels–Alder approaches, 159–161
7-oxanorbornane skeleton, 142–143
preparation, 143–144
reactions
acid-induced ethereal bridge
nucleophilic displacements,
167–170
base-induced ethereal bridge opening,
170–172
carbon–carbon bonds cleavage,
177–182
chalconide and halide/metal exchange,
174–177
reductive ethereal ring opening,
172–174
sesquiterpenoid, 147–150
triterpenoid, 153–158
Oxacycle synthesis
eight-membered
benzooxocin ring system, 331
Brevetoxin A, 334, 337
Claisen–Ireland rearrangement, 330
conformational reorganization, 328
CTX3C synthesis, 334
enantioselective total synthesis,
331, 332
gauche effect, 325, 326
heliannuols, benzooxocin core, 331, 332
Laurencia oxacycles, 325
(+)-laurencin, 325, 326
octalactins, 332, 333
(+)-prelaureatin, 327, 328
RCM, protecting groups, 328, 329
relative stereochemistry, 329, 330
solandelactones, cyclopropyl lactone,
333, 334
tributylstannyl group, 329, 330
nine-membered
eleutherobin, B-ring, 336, 337
formation, 336
gambieric acids, 340
(–)-halicholacton, 338
halicholactone, 337
isolaurallene synthesis, 336
(+)-obtusenyne synthesis, 337
oxoninoquinolones, 338
polycyclic ether skeletons, 341
relative stereochemistry effect, 339, 340
topsentolide B 3 , stereoselective
synthesis, 338, 339
ten-membered
C1–C7 fragment synthesis, 341, 342
description, 341
microcarpalide synthesis, 342
olefin geometry, catalyst effect,
343–344
Oxa-Michael cyclization, 229, 294–295
bis(benzannulated) spiroacetals, 229, 231
cascade approaches, 232
desymmetrization/oxa-Michael addition,
230, 232
norhalichondrin B, 229, 230
Oxidative cyclizations, tetrahydrofurans
cobalt catalyzed, 19
intramolecular iodoetherification, 25, 26
manganese-mediated, 21–23
osmium-catalyzed, 23–26
palladium catalyzed, 19, 20
ruthenium catalyzed, 20–21
Oxocines, 357
Oxonium ylide approach, 18
Oxygenated nucleophiles, 288–291
Oxygenated structures, ring expansion
bicyclo[4.1.0] heptanes, cyclopropanation
and ring opening, 284–286
2-halomethyl cyclic ethers, 289
4-methylene-chromanes, 287, 288
pyranones, Arndt–Eistert reaction, 286, 287
Index
435
endo conjugate addition approach, 48
leucascandrolide A, 48
phorboxazole A, 51, 52
(+)-SCH 351448, 48, 49
spongistatin 1, 50, 51
stereochemical consequences, 46, 47
nucleophilic substitution cyclizations
epoxide opening, 59–61
leucascandrolide A, 53
mechanistic considerations, 52, 53
phorboxazoles, 54, 55
spongistatin 1, 53, 54
One-pot reaction, 24, 25
Organocatalytic aldol-Michael reactions, 7
Osmium-catalyzed cyclizations
aminohydroxylation strategy, 24
(+)-cis-solamin, 23, 24
(Z,Z)-diene cyclizations, 25, 26
OsO 4 , 23
7-Oxabicyclo[2.2.1]heptane
cantharidin and analogues, 144–145
with carotenoids, 158–159
Diels–Alder approaches, 161–166
diterpenoid, 150–153
monoterpenoid, 145–147
non-Diels–Alder approaches, 159–161
7-oxanorbornane skeleton, 142–143
preparation, 143–144
reactions
acid-induced ethereal bridge
nucleophilic displacements,
167–170
base-induced ethereal bridge opening,
170–172
carbon–carbon bonds cleavage,
177–182
chalconide and halide/metal exchange,
174–177
reductive ethereal ring opening,
172–174
sesquiterpenoid, 147–150
triterpenoid, 153–158
Oxacycle synthesis
eight-membered
benzooxocin ring system, 331
Brevetoxin A, 334, 337
Claisen–Ireland rearrangement, 330
conformational reorganization, 328
CTX3C synthesis, 334
enantioselective total synthesis,
331, 332
gauche effect, 325, 326
heliannuols, benzooxocin core, 331, 332
Laurencia oxacycles, 325
(+)-laurencin, 325, 326
octalactins, 332, 333
(+)-prelaureatin, 327, 328
RCM, protecting groups, 328, 329
relative stereochemistry, 329, 330
solandelactones, cyclopropyl lactone,
333, 334
tributylstannyl group, 329, 330
nine-membered
eleutherobin, B-ring, 336, 337
formation, 336
gambieric acids, 340
(–)-halicholacton, 338
halicholactone, 337
isolaurallene synthesis, 336
(+)-obtusenyne synthesis, 337
oxoninoquinolones, 338
polycyclic ether skeletons, 341
relative stereochemistry effect, 339, 340
topsentolide B 3 , stereoselective
synthesis, 338, 339
ten-membered
C1–C7 fragment synthesis, 341, 342
description, 341
microcarpalide synthesis, 342
olefin geometry, catalyst effect,
343–344
Oxa-Michael cyclization, 229, 294–295
bis(benzannulated) spiroacetals, 229, 231
cascade approaches, 232
desymmetrization/oxa-Michael addition,
230, 232
norhalichondrin B, 229, 230
Oxidative cyclizations, tetrahydrofurans
cobalt catalyzed, 19
intramolecular iodoetherification, 25, 26
manganese-mediated, 21–23
osmium-catalyzed, 23–26
palladium catalyzed, 19, 20
ruthenium catalyzed, 20–21
Oxocines, 357
Oxonium ylide approach, 18
Oxygenated nucleophiles, 288–291
Oxygenated structures, ring expansion
bicyclo[4.1.0] heptanes, cyclopropanation
and ring opening, 284–286
2-halomethyl cyclic ethers, 289
4-methylene-chromanes, 287, 288
pyranones, Arndt–Eistert reaction, 286, 287
Index
435