4-(3-吡啶基)-1H-咪唑的合成

3-溴乙酰基吡啶经DMSO氧化制得吡啶基乙酮醛,不经纯化,与乙酸铵和甲醛经Debus-Radziszewski环合反应制得泰利霉素侧链4-(3-吡啶基)-1H-咪唑,总收率约66％.     

2,4-二甲基-5-甲酰基-1H-吡咯-3-甲酸的合成

乙酰乙酸叔丁酯经系列反应得到的氨基酮与乙酰乙酸乙酯经Knorr反应得2，4-二甲基-3-乙氧羰基-1H-吡咯-5-羧酸叔丁酯，再经甲酰化、水解得抗肿瘤药舒尼替尼的重要中间体2，4-二甲基-5-甲酰基-1H-吡咯-3-甲酸，总收率约为44％。     

N-(4-氯-3-三氟甲基苯基)-N'-(4-溴苯基)脲的合成

4-氯-3-三氟甲基苯胺和三光气在乙酸乙酯中反应制得4-氯-3-三氟甲基苯异氰酸酯,不经分离纯化,直接与对溴苯胺反应制得抗肿瘤药索拉非尼的中间体N-(4-氯-3-三氟甲基苯基)-N'-(4-溴苯基)脲,总收率约75%,纯度99.8%.     

4-(1-羟基-1-甲基乙基)-2-丙基-1H-咪唑-5-羧酸乙酯的合成

2-甲基-2-羟基丙腈(2)经三甲基硅基(TMS)保护后,经Blaise反应并脱三甲基硅烷基保护,在亚硝酸钠和乙酸作用下肟化和Pd/C催化还原得到2-氨基-4-羟基-4-甲基-3-氧代戊酸乙酯三氟乙酸盐,再与丁酰亚氨酸甲酯盐酸盐环合得到奥美沙坦酯关键中间体4-(1-羟基-1-甲基乙基)-2-丙基-1H-咪唑-5-羧酸乙酯,总收率约40%。     

4-[4-(吡啶-3-基)咪唑-1-基]丁胺的合成

以3-乙酰基吡啶为起始原料,经肟化、磺酰化、氧化、环合、还原得到3-(咪唑-4-基)吡啶,再经与N-(4-溴丁基)邻苯二甲酰亚胺缩合及肼解等反应制得抗菌剂泰利霉素的特定侧链化合物4-[4-(吡啶-3-基)咪唑-1-基]丁胺,总收率24%.     

间三氟甲基苯胺的合成

以三氟甲苛来起始原料，经混酸硝化和加氢还原反应合成间三氟甲基苯胺，总收率达８３％，产品纯度９８％以上。     

间三氟甲基苯胺的合成

以三氟甲苯为起始原料,经混酸硝化和加氢还原反应合成间三氟甲基苯胺,总收率达83%,产品纯度98%以上。     

1-三苯基甲基-4-咪唑甲醛的合成

1-三苯基甲基 - 4-咪唑甲醛 ( 1 )是合成正处于 期临床的抗癌药 girolline[1]、组氨酸及其衍生物的重要中间体[2 ,3 ] 。可用 1 -三苯甲基 - 4-碘咪唑与 DMF反应得到 ,产率 83% [4] ,但需用正丁基锂及低温( - 78℃ )反应 ,原料和试剂价格昂贵。也有报道用4,5 -咪唑二羧酸为原料 ,经二聚、脱羧、酯化、N-烷基化、还原反应得到中间体 1 -三苯甲基 - 4-咪唑甲醇 ,但路线长 ,收率 62 % [5] 。本文参考文献[6,7] ,以果糖 ( 2 )为原料 ,经环合、氧化和 N -烷基化制得 1 ,并进行了改进。 4的制备将文献 [7]需将 3转化为盐酸盐改为由 3直接氧化得…     

3-溴-4-甲氧基苯胺的合成

用对氟硝基苯为原料,经N-溴代丁二酰亚胺溴代制得3-溴-4-氟硝基苯,经甲醇钠醚化制得3-溴-4-甲氧基硝基苯后,再经硫化钠还原制得3-溴-4-甲氧基苯胺,总收率约63%。     

2-氯-4-(哌啶-1-基甲基)吡啶的合成

2-氨基-4-甲基吡啶在过量浓盐酸/亚硝酸钠作用下与氯化亚铜/盐酸反应后,在偶氮二异丁腈(AIBN)作用下与硫酰氯反应制得2-氯-4-(氯甲基)吡啶,再在DMF中与哌啶缩合,得到拉呋替丁的关键中间体2-氯-4-(哌啶-1-基甲基)-吡啶,总收率约62％.     

Cardiotonic agents. 7. Prodrug derivatives of 4-ethyl-1,3-dihydro- 5-[4-(2-methyl-1H-imidazol-1-yl)benzoyl]-2H-imidazol-2-one.

The cardiotonic agent 4-ethyl-1,3-dihydro-5-4-(2-methyl-1H-imidazol-1-yl)benzoyl]-2H- imidazol-2-one (1) was found to have low bioavailability when administered orally to rats and dogs. A series of N-acyl derivatives, an underutilized prodrug of acidic NH compounds, has been synthesized and tested for their ability to improve the oral bioavailability of 1. Reaction of the monosodium salt of 1 with various anhydrides afforded the N-1 monoacylimidazolones with surprisingly high regioselectivity. In addition to the prodrugs, acylation of 1 with propionic or phenylacetic anhydride led to the novel 3H-pyrrolo[1,2-c]imidazole-3,5(2H)-diones 6. The prodrugs showed a significant increase in the partition coefficients with a minor decrease in the aqueous solubility. The benzoyl derivative 4b exhibited the highest stability in both pH 1.5 and 7.4 buffer solutions. Further evaluation of 4b showed rapid conversion to 1 in canine plasma (t1/2 = 38 min), and human plasma (t1/2 = 10 min). Oral studies indicated that the bioavailability of 4b was increased to greater than 75% (compared to less than 20% for 1), and hemodynamic studies demonstrated that the selective inotropic profile of 1 was retained.     

Cardiotonic agents. 5. 1,2-Dihydro-5-[4-(1H-imidazol-1-yl)phenyl]-6-methyl-2-oxo-3- pyridinecarbonitriles and related compounds. Synthesis and inotropic activity

Several 1,2-dihydro-5-(substituted phenyl)-2(1H)-pyridinones were synthesized and evaluated for inotropic activity. 1,2-Dihydro-5-[4-(1H-imidazol-1-yl)phenyl]-6-methyl-2-oxo-3- pyridinecarbonitrile (5a) and the corresponding unsubstituted analogue 14a were the most potent positive inotropic agents in this series. Although the 4,6-dimethyl analogue 6a retained most of the activity of 5a, the 4-methyl analogue 8a was substantially less potent. The synthesis and structure-activity relationships are discussed.     

Cardiotonic agents. 3. Synthesis and biological activity of novel 6-(substituted 1H-imidazol-4(5)-yl)-3(2H)-pyridazinones

Several 6-(substituted 1H-imidazol-4(5)-yl)-3(2H)-pyridazinones were synthesized and evaluated for positive inotropic activity. The 1H-imidazol-4-yl regioisomers 4,5-dihydro-6-(1-methyl-2-phenyl-1H-imidazol-4-yl)-3(2H)-pyridazinone (25a) and 6-(1-methyl-2-phenyl-1H-imidazol-4-yl)-3(2H)-pyridazinone (28a) were potent positive inotropic agents. By contrast, the corresponding 1H-imidazol-5-yl regioisomers 25b and 28b were only weak positive inotropic agents. Compounds 25a and 28a were also potent inhibitors of cardiac phosphodiesterase fraction III.     

A selective human H(4)-receptor agonist: (-)-2-cyano-1-methyl-3-[(2R,5R)-5- [1H-imidazol-4(5)-yl]tetrahydrofuran-2-y] methylguanidine

A series of 16 compounds related to chiral 4(5)-(5-aminomethyltetrahydrofuran-2-yl)imidazoles (1) have been designed, synthesized, and examined in vitro by radioligand displacement studies and functional assays for both the human H(3)- and H(4)-receptors expressed in SK-N-MC cells. Among them, the (2S,5S)-isomer 1d of amino compounds showed approximately 300-fold higher selectivity at the H(3)-receptor than the H(4)-receptor. On the other hand, (2R,5S)- and (2R,5R)-cyanoguanidines 3b and 3c, in which the amino group of the compounds 1b and 1c was substituted by the cyanoguanidino moiety, bound to the H(4)-receptor with a pEC(50) value of 6.65 and 7.11, respectively, and had >40-fold selectivities over the H(3)-receptor. As such, 3b and 3c are the first selective H(4) receptor agonists.     

4-[4-(3,4-亚甲二氧基苯基)-5-(2-吡啶基)-1H咪唑-2-基]苯甲酰胺的合成工艺改进

目的改进4-[4-(3,4-亚甲二氧基苯基)-5-(2-吡啶基)-1H-咪唑-2-基]苯甲酰胺(SB-431542)的合成工艺.方法关键中间体4-[4-(3,4-亚甲二氧基苯基)-5-(2-吡啶基)-N-1-羟基咪唑-2-基]苯腈(1)以三氯化肽[Ti(Ⅲ)Cl3]还原得到4-[4-(3,4-亚甲二氧基苯基)-5-(2-吡啶基)-1H-咪唑-2-基]苯腈(2);2在叔丁醇中以氢氧化钾水解将腈基转化为胺酰基得到了SB-431542.结果与讨论中间体和终产物经1H-NMR和MS鉴定,均与文献的数据相符.该合成工艺缩短了合成路线、简化了操作、提高了收率和纯度,避免了使用毒性大的亚磷酸三乙酯[P(OEt)3].     

Urinary metabolites of 3a,4,5,6,7,7a-hexahydro-3-(1-methyl-5-nitro-1H-imidazol-2-yl)-1,2-benzisoxazole in the dog.

The antiprotozoal drug 3a,4,5,6,7,7a-hexahydro-3-(1-methyl-5-nitro-1H-imidazol-2-yl)-1,2-benzisoxazole (I), which exhibits activity against trypanosomiasis, is also antibacterial in vivo. Since the urine from a dog dosed with I showed a broader spectrum of antibacterial activity than I itself, metabolites from this urine were isolated and partially characterized. The metabolites were mono- and dihydroxy-substituted species with the hydroxyl groups on carbons 4--7 of the hexahydrobenzisoxazole ring. These observations led to the synthesis of several such hydroxy derivatives of I, and their properties fully supported the proposed positions of metabolic hydroxylation. One synthetic compound, the 6,7-cis-dihydroxy compound, exhibited higher antibacterial activity against Salmonella schottmuelleri in mice and greater trypanocidal activity in vivo against Trypanosoma cruzi (Brazil strain) than I.     

咪苯嗪酮对花生四烯酸诱导的大鼠脑血栓形成的影响

花生四烯酸(AA)0.25～1 mg·kg~(-1)经颈内动脉注射能诱发大鼠同侧大脑半球脑内血栓形成,明显增加伊文思蓝通过血脑屏障渗入脑实质的量,峰值为205±s 50 mg·kg~1脑组织,相应对照组为10±s 5mg·kg~1,咪苯嗪酮0.25～0.5mg·kg~1 iv能对抗AA引起的大鼠脑血栓形成,显著降低脑实质内伊文思蓝的含量,作用呈剂量依赖性,且强于哒唑氧苯     

2-(2-苄氧羰基氨基噻唑-4-基)-5-(3-甲基-2-丁烯氧羰基)-2-戊烯酸的合成

对头孢布烯的关键中间体2-(2-苄氧羰基氨基噻唑-4-基)-5-(3-甲基-2-丁烯氧羰基)-2-戊烯酸(1)的合成工艺进行了研究。选用国内易得的(2-氨基噻唑-4-基)乙酸甲酯(2)作为起始原料,经过氨基保护、M ichae l加成-消除和选择性酯化三步反应制得目标化合物1,反应总收率63.0%。该工艺操作简单,生产成本低,适合工业化生产。