【结 构 式】 |
【分子编号】63624 【品名】methyl 3-thioxo-2,3,6,11-tetrahydro-1H-indolizino[8,7-b]indole-11b(5H)-carboxylate 【CA登记号】 |
【 分 子 式 】C16H16N2O2S 【 分 子 量 】300.38132 【元素组成】C 63.98% H 5.37% N 9.33% O 10.65% S 10.68% |
合成路线1
该中间体在本合成路线中的序号:(I)In a nonoxidative coupling sytrategy, the required tetracyclic precursor (X) has been prepared by two methods. Alkylation of thiolactam (I) with 2 (bromomethyl)-1-butene (II) gives the thioiminium salt (III), which undergoes thio-Claisen rearrangement in the presence of DBU in THF to produce (IV) as a mixture of cis and trans isomers. After conversion of thiolactams (IV) into the corresponding lactams with m-chloroperoxybenzoic acid (mCPBA), the desired isomer (V) is isolated employing preparative HPLC. Double bond dihydroxylation with N-methylmorpholine-N-oxide in the presence of a catalytic amount of OsO4 leads to diol (VI) as a diastereomeric mixture. Protection of diols (VI) with 1-methoxycyclohexene (VII) affords the corresponding mixture of cyclohexylidene ketals (VIII). After conversion of (VIII) to the respective thiolactams with Lawesson's reagent in hot toluene, separation of isomers employing preparative HPLC furnishes thiolactam (IX). Then, desulfuration of thiolactam (IX) by means of Raney nickel gives rise to intermediate (X) (7).
【1】 Magnus, P.; Mendoza, J.S.; Stamford, A.; Ladlow, M.; Willis, P.; Nonoxidative coupling methodology for the synthesis of the antitumor bisindole alkaloid vinblastine and a lower-half analogue: Solvent effect on the stereochemistry of the crucial C-15/C-18' bond. J Am Chem Soc 1992, 114, 26, 10232. |
中间体序号 | 中间体编号 | 品名 | CAS号 | 分子式 | 供应商 | 用于合成 |
---|---|---|---|---|---|---|
(I) | 63624 | methyl 3-thioxo-2,3,6,11-tetrahydro-1H-indolizino[8,7-b]indole-11b(5H)-carboxylate | C16H16N2O2S | 详情 | 详情 | |
(II) | 63625 | C5H9Br | 详情 | 详情 | ||
(III) | 63626 | {11b-[(methyloxy)carbonyl]-1,2,5,6,11,11b-hexahydro-3H-indolizino[8,7-b]indol-3-ylidene}(2-ethyl-2-propenyl)sulfonium bromide | C21H25BrN2O2S | 详情 | 详情 | |
(IV) | 63627 | methyl 2-(2-ethyl-2-propenyl)-3-thioxo-2,3,6,11-tetrahydro-1H-indolizino[8,7-b]indole-11b(5H)-carboxylate | C21H24N2O2S | 详情 | 详情 | |
(V) | 63628 | methyl 2-(2-ethyl-2-propenyl)-3-oxo-2,3,6,11-tetrahydro-1H-indolizino[8,7-b]indole-11b(5H)-carboxylate | C21H24N2O3 | 详情 | 详情 | |
(VI) | 63629 | methyl 2-[2-hydroxy-2-(hydroxymethyl)butyl]-3-oxo-2,3,6,11-tetrahydro-1H-indolizino[8,7-b]indole-11b(5H)-carboxylate | C21H26N2O5 | 详情 | 详情 | |
(VII) | 63630 | 1-(methyloxy)-1-cyclohexene; 1-cyclohexen-1-yl methyl ether | C7H12O | 详情 | 详情 | |
(VIII) | 63631 | methyl 2-[(2-ethyl-1,4-dioxaspiro[4.5]dec-2-yl)methyl]-3-oxo-2,3,6,11-tetrahydro-1H-indolizino[8,7-b]indole-11b(5H)-carboxylate | C27H34N2O5 | 详情 | 详情 | |
(IX) | 63632 | methyl 2-[(2-ethyl-1,4-dioxaspiro[4.5]dec-2-yl)methyl]-3-thioxo-2,3,6,11-tetrahydro-1H-indolizino[8,7-b]indole-11b(5H)-carboxylate | C27H34N2O4S | 详情 | 详情 | |
(X) | 63633 | methyl 2-[(2-ethyl-1,4-dioxaspiro[4.5]dec-2-yl)methyl]-2,3,6,11-tetrahydro-1H-indolizino[8,7-b]indole-11b(5H)-carboxylate | C27H36N2O4 | 详情 | 详情 |
合成路线2
该中间体在本合成路线中的序号:(I)In an alternative, stereospecific synthesis of (X), Sharpless asymmetric epoxidation of 2-ethyl-2-propen-1-ol (XI) in the presence of (-)-diethyl tartrate provides the (R)-epoxide (XII). Ring opening of (XII) with sodium thiophenoxide produces diol (XIII), which is further protected with 1-methoxycyclohexene (VII), yielding ketal (XIV). Sulfide (XIV) is then oxidized with mCPBA to afford sulfoxide (XV) as a mixture of diastereoisomers. Pummerer rearrangement of sulfoxides (XV) in boiling Ac2O, followed by alkaline hydrolysis of the intermediate alpha-acetoxy sulfides furnishes aldehyde (XVI). Then, aldol condensation of aldehyde (XVI) with thiolactam (I) employing stannous triflate and N-ethylpiperidine gives adduct (XVII). Dehydration of alcohol (XVII) to the alpha,beta-unsaturated thiolactam (XVIII) is accomplished by tosylation with p-toluenesulfonic anhydride, followed by tosylate elimination in the presence of DBU. Desulfuration of thiolactam (XVIII) with deactivated Ra-Ni leads to (XIX). Then, hydrogenation of olefin (XIX) produces a mixture of epimers, from which the target isomer (X) can be isolated by column chromatography (7).
【1】 Magnus, P.; Mendoza, J.S.; Stamford, A.; Ladlow, M.; Willis, P.; Nonoxidative coupling methodology for the synthesis of the antitumor bisindole alkaloid vinblastine and a lower-half analogue: Solvent effect on the stereochemistry of the crucial C-15/C-18' bond. J Am Chem Soc 1992, 114, 26, 10232. |
中间体序号 | 中间体编号 | 品名 | CAS号 | 分子式 | 供应商 | 用于合成 |
---|---|---|---|---|---|---|
(I) | 63624 | methyl 3-thioxo-2,3,6,11-tetrahydro-1H-indolizino[8,7-b]indole-11b(5H)-carboxylate | C16H16N2O2S | 详情 | 详情 | |
(VII) | 63630 | 1-(methyloxy)-1-cyclohexene; 1-cyclohexen-1-yl methyl ether | C7H12O | 详情 | 详情 | |
(X) | 63633 | methyl 2-[(2-ethyl-1,4-dioxaspiro[4.5]dec-2-yl)methyl]-2,3,6,11-tetrahydro-1H-indolizino[8,7-b]indole-11b(5H)-carboxylate | C27H36N2O4 | 详情 | 详情 | |
(XI) | 63603 | 2-ethyl-2-propen-1-ol | C5H10O | 详情 | 详情 | |
(XII) | 63604 | (2-ethyl-2-oxiranyl)methanol | C5H10O2 | 详情 | 详情 | |
(XIII) | 63634 | 2-[(phenylsulfanyl)methyl]-1,2-butanediol | C11H16O2S | 详情 | 详情 | |
(XIV) | 63635 | 2-ethyl-2-[(phenylsulfanyl)methyl]-1,4-dioxaspiro[4.5]decane; (2-ethyl-1,4-dioxaspiro[4.5]dec-2-yl)methyl phenyl sulfide | C17H24O2S | 详情 | 详情 | |
(XV) | 63636 | (2-ethyl-1,4-dioxaspiro[4.5]dec-2-yl)methyl phenyl sulfoxide; 2-ethyl-2-[(phenylsulfinyl)methyl]-1,4-dioxaspiro[4.5]decane | C17H24O3S | 详情 | 详情 | |
(XVI) | 63637 | C11H18O3 | 详情 | 详情 | ||
(XVII) | 63638 | methyl 2-[(2-ethyl-1,4-dioxaspiro[4.5]dec-2-yl)(hydroxy)methyl]-3-thioxo-2,3,6,11-tetrahydro-1H-indolizino[8,7-b]indole-11b(5H)-carboxylate | C27H34N2O5S | 详情 | 详情 | |
(XVIII) | 63639 | methyl 2-[(2-ethyl-1,4-dioxaspiro[4.5]dec-2-yl)methylidene]-3-thioxo-2,3,6,11-tetrahydro-1H-indolizino[8,7-b]indole-11b(5H)-carboxylate | C27H32N2O4S | 详情 | 详情 | |
(XIX) | 63640 | methyl 2-[(2-ethyl-1,4-dioxaspiro[4.5]dec-2-yl)methylidene]-2,3,6,11-tetrahydro-1H-indolizino[8,7-b]indole-11b(5H)-carboxylate | C27H34N2O4 | 详情 | 详情 |