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【结 构 式】 
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【分子编号】24113 【品名】methyl 3-methyl-2-butenoate; Methyl 3,3-dimethylacrylate 【CA登记号】924-50-5 |
【 分 子 式 】C6H10O2 【 分 子 量 】114.1442 【元素组成】C 63.14% H 8.83% O 28.03% |
合成路线1
该中间体在本合成路线中的序号：(II)Coupling of 2,5-dimethylphenol (I) with methyl 3,3-dimethylacrylate (II) by means of methanesulfonic acid yields dihydrocoumarin (III), which is reduced with LiAlH4 in THF to provide alcohol (IV). Selective O-protection at the primary hydroxy group of (IV) with tert-butyldimethylsilyl chloride (TBDMS-Cl) and Et3N in dichloromethane affords compound (V), which is then coupled with Boc-Ala-OH (VI) by means of EDC and DMAP in dichloromethane to give ester (VII). O-Deprotection of (VII) with HOAc in THF/H2O furnishes alcohol (VIII), which is then oxidized by means of pyridinium chlorochromate (PCC) in dichloromethane, giving aldehyde (IX). Compound (IX) is further oxidized with NaClO2 and sodium sulfite (Na2CO3) in H2O and NaH2PO4 in acetonitrile to yield propionic acid (X), whose Boc group is removed by treatment with TFA in dichloromethane, furnishing hydrochloride (XI). Coupling of (XI) with PEG thiazolidinethione (T-PEG) (XII) (1) by means of DIEA in dichloromethane gives PEG-alaninyl derivative (XIII), which is finally condensed with daunorubicin hydrochloride (XIV) by means of EDC · HCl, HOBt and NMM in dichloromethane to afford the target product.
| 【1】 Greenwald, R.B.; et al.; PEG thiazolidine-2-thione, a novel reagent for facile protein modification: Conjugation of bovine hemoglobin. Bioconjugate Chem 1996, 7, 6, 638. |
| 【2】 Choe, Y.H.; Shum, K.; Conover, C.D.; Greenwald, R.B.; Wu, D.; Royzen, M.; Drug delivery systems based on trimethyl lock lactonization: Poly(ethylene glycol) prodrugs of amino-containing compounds. J Med Chem 2000, 43, 3, 475. |
| 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) | 46786 | 3,5-dimethylphenol | 108-68-9 | C8H10O | 详情 | 详情 |
| (II) | 24113 | methyl 3-methyl-2-butenoate; Methyl 3,3-dimethylacrylate | 924-50-5 | C6H10O2 | 详情 | 详情 |
| (III) | 46787 | 4,4,5,7-tetramethyl-2-chromanone | C13H16O2 | 详情 | 详情 | |
| (IV) | 46788 | 2-(3-hydroxy-1,1-dimethylpropyl)-3,5-dimethylphenol | C13H20O2 | 详情 | 详情 | |
| (V) | 46789 | 2-(3-[[tert-butyl(dimethyl)silyl]oxy]-1,1-dimethylpropyl)-3,5-dimethylphenol | C19H34O2Si | 详情 | 详情 | |
| (VI) | 26450 | Boc-L-Alanine;(S)-2-((tert-butoxycarbonyl)amino)propanoic acid;N-Boc-L-alanine; (2S)-2-[(tert-butoxycarbonyl)amino]propionic acid | 15761-38-3 | C8H15NO4 | 详情 | 详情 |
| (VII) | 46790 | 2-(3-[[tert-butyl(dimethyl)silyl]oxy]-1,1-dimethylpropyl)-3,5-dimethylphenyl (2S)-2-[(tert-butoxycarbonyl)amino]propanoate | C27H47NO5Si | 详情 | 详情 | |
| (VIII) | 46791 | 2-(3-hydroxy-1,1-dimethylpropyl)-3,5-dimethylphenyl (2S)-2-[(tert-butoxycarbonyl)amino]propanoate | C21H33NO5 | 详情 | 详情 | |
| (IX) | 46792 | 2-(1,1-dimethyl-3-oxopropyl)-3,5-dimethylphenyl (2S)-2-[(tert-butoxycarbonyl)amino]propanoate | C21H31NO5 | 详情 | 详情 | |
| (X) | 46793 | 3-[2-([(2S)-2-[(tert-butoxycarbonyl)amino]propanoyl]oxy)-4,6-dimethylphenyl]-3-methylbutyric acid | C21H31NO6 | 详情 | 详情 | |
| (XI) | 46794 | 3-(2-[[(2S)-2-aminopropanoyl]oxy]-4,6-dimethylphenyl)-3-methylbutyric acid | C16H23NO4 | 详情 | 详情 | |
| (XII) | 46795 | 2-(2-methoxyethoxy)-1-(2-thioxo-1,3-thiazolidin-3-yl)-1-ethanone | C8H13NO3S2 | 详情 | 详情 | |
| (XIII) | 46796 | 3-[2-[((2S)-2-[[2-(2-methoxyethoxy)acetyl]amino]propanoyl)oxy]-4,6-dimethylphenyl]-3-methylbutyric acid | C21H31NO7 | 详情 | 详情 | |
| (XIV) | 18598 | 2-methyl-8-quinolinol | 826-81-3 | C10H9NO | 详情 | 详情 |
合成路线2
该中间体在本合成路线中的序号：(XXXIX)The dehydro precursors (XXIa) and (XXIb) are prepared by the following sequences. Allylic bromination of β-cyclocitral (XXXVII) with N-bromosuccinimide in cold CH2Cl2 in the presence of CaO and NaHCO3 followed by elimination of HBr in boiling collidine gives α-safranal (XXXVIII). Subsequent cyclization of aldehyde (XXXVIII) with the lithium carbanion derived from ethyl 3,3-dimethylacrylate (XXXIX) in cold THF provides lactone (XLa). The analogous lactone containing an unconjugated cyclohexadiene ring (XLb) is obtained by MichaelWittig tandem reaction of ethyl 2-isopropylideneacetoacetate (XLI) with the phosphorous ylide derived from allyltriphenylphosphonium chloride (XLII) to produce the cyclic ester (XLIII). Subsequent LiAlH4 reduction of ester (XLIII) followed by Swern oxidation gives aldehyde (XLIV). After isomerization of aldehyde (XLIV) upon treatment with catalytic DBU in CH2Cl2 at room temperature, the isomeric cyclohexadienal (XLV) is condensed with ethyl 3,3-dimethylacrylate (XXXIX) as above to furnish lactone (XLb). Reduction of either lactone (XLa) or (XLb) with DIBALH followed by acid-catalyzed ring opening of the resulting lactols leads to the respective tetraenic aldehydes (XLVIa) and (XLVIb), which undergo Horner-Emmons olefination with diethyl 3-(ethoxycarbonyl)-2-methylprop-2-enylphosphonate (XIII) to furnish the corresponding esters (XXIa) and (XXIb) (9). Scheme 4.
| 【9】 Bennani, Y.L., Boehm, M.F. Synthesis of high specific activity 2,3- and 3,4-[3H]2-9-cis-retinoic acid. J Org Chem 1995, 60(5): 1195-200. |
| 中间体序号 | 中间体编号 | 品名 | CAS号 | 分子式 | 供应商 | 用于合成 |
|---|---|---|---|---|---|---|
| (Xla) | 65514 | C15H20O2 | 详情 | 详情 | ||
| (XLb) | 65515 | C15H20O2 | 详情 | 详情 | ||
| (XLVIa) | 65521 | C15H20O | 详情 | 详情 | ||
| (XLVIb) | 65522 | C15H20O | 详情 | 详情 | ||
| (XIII) | 44704 | ethyl (E)-4-(diethoxyphosphoryl)-3-methyl-2-butenoate | 41891-54-7 | C11H21O5P | 详情 | 详情 |
| (XXI) | 65496 | C22H30O2 | 详情 | 详情 | ||
| (XXXVII) | 65512 | beta-Cyclocitral; 2,6,6-Trimethyl-1-Cyclohexenecarboxaldehyde; Ai3-37227 | 432-25-7 | C10H16O | 详情 | 详情 |
| (XXXVIII) | 65513 | 2,6,6-Trimethyl-1,3-Cyclohexadiene-1-Carboxaldehyde | 116-26-7 | C10H14O | 详情 | 详情 |
| (XXXIX) | 24113 | methyl 3-methyl-2-butenoate; Methyl 3,3-dimethylacrylate | 924-50-5 | C6H10O2 | 详情 | 详情 |
| (XLI) | 65516 | ethyl 2-isopropylideneacetoacetate | C9H14O3 | 详情 | 详情 | |
| (XLII) | 65517 | allyltriphenylphosphonium chloride | C21H20ClP | 详情 | 详情 | |
| (XLIII) | 65518 | C12H18O2 | 详情 | 详情 | ||
| (XLIV) | 65519 | C10H13O | 详情 | 详情 | ||
| (XLV) | 65520 | C10H13O | 详情 | 详情 |