18903-18-9

基本信息
5-氨基噻唑-4-羧酸乙酯
5-氨基噻唑-4-甲酸乙酯
5-氨基噻唑-4-甲酸乙酯 1KG
2-Pyrrolidinone,6-(hydroxymethyl)-
Ethyl 5-aMino-1,3-thiazole-4-carboxylate
5-Aminothiazole-4-carboxylic acid ethyl ester
4-Thiazolecarboxylic acid, 5-aMino-, ethyl ester
ethyl 5-aminothiazole-4-carboxylate hydrochloride
物理化學(xué)性質(zhì)
制備方法

1759-25-7

18903-18-9
化合物16c的合成:5-氨基噻唑-4-羧酸乙酯的制備:將化合物16b(9.0g,58mmol)懸浮于甲苯(200ml)中。一次性加入Lawesson試劑(23.0g,58mmol,1當量)。將所得黃色懸浮液在70℃及N2氣氛下攪拌過夜。反應(yīng)完成后,將混合物冷卻至0℃,從燒瓶底部的膠狀物質(zhì)中傾析出甲苯層,并用1N鹽酸水溶液(6×50ml)洗滌。將膠狀物質(zhì)溶解于甲醇(150ml)中,隨后減壓濃縮。將殘余物(棕色油狀物)懸浮于叔丁基甲基醚(TBME,300ml)中,并用1N鹽酸水溶液(1×300ml,2×100ml)洗滌。合并水相部分,用2N氫氧化鈉水溶液(460ml)堿化,隨后用乙酸乙酯(EtOAc,1×300ml,2×200ml和1×100ml)萃取。合并有機層,用無水硫酸鈉(Na2SO4)干燥,過濾后減壓濃縮,得到粗品5-氨基噻唑-4-甲酸乙酯(7g)。粗產(chǎn)物通過柱色譜法(硅膠,庚烷-乙酸乙酯,1/1)純化,得到化合物16c(6g,35mmol,60%收率),為棕色固體。1H-NMR(300MHz,CDCl3)δ 7.89(s,1H),6.04(bs,2H),4.42(q,2H,J=7Hz),1.43(t,3H,J=7Hz)。
參考文獻:
[1] Patent: WO2008/59368, 2008, A2. Location in patent: Page/Page column 66-68
[2] Patent: WO2014/33630, 2014, A1. Location in patent: Page/Page column 50
[3] Bioorganic and Medicinal Chemistry, 2015, vol. 23, # 13, p. 3774 - 3780
[4] Nucleosides and Nucleotides, 1995, vol. 14, # 3-5, p. 313 - 316
[5] Chemical and Pharmaceutical Bulletin, 1971, vol. 19, p. 119 - 123