2-Polyfluoroalkylchromones. 14. Synthesis of 4-chloro-3(5)-(2-hydroxyaryl)-5(3)-polyfluoroalkylpyrazoles

3-Chloro-2-polyfluoroalkyl- and 3-chloro-6-nitro-2-polyfluoroalkylchromones were synthesized. These compounds react with N₂H₄·2HCl on boiling in ethanol to form 4-chloro-3(5)-(2-hydroxyaryl)-5(3)-polyfluoroalkylpyrazoles.     

Synthesis of 1-(2,4,6-trichlorophenyl)-3-(3-nitro- and 2-chloro-5-nitroanilino)-5-pyrazolones

A convenient one flask synthesis of 1-aryl-3-nitroanilino-5-pyrazolones in yields of 60–65% is described. Synthesis involves initial reaction of ethyl 3-ethoxy-3-iminopropionate hydrochloride and a nitroaniline in methanol producing an imidate ester. The imidate ester is then reacted with an arylhydrazine forming an amidine. The amidine is then cyclized with base.     

Practical synthesis of methyl(E)-2-(3-(3-(2-(7-chloro-2- quinolinyl)ethenyl)phenyl)-3-oxopropyl)benzoate,a key intermediate of Montelukast

A novel and practical synthetic route is presented for the preparation of methyl-(E)-2-(3-(3-(2-(7-chloro-2-quinolinyl)ethenyl) phenyl)-3-oxopropyl)benzoate,the key intermediate of Montelukast,a leukotriene antagonist.The main diarylpropane framework was prepared via a polarity conversation reaction resulting in an acyl anion equivalent followed by a nucleophilic substitution reaction.The overall yield of this approach was 61%.This method is simple for operation and suitable for industrial production.     

Synthesis of new modified aza heterocycles on the basis of 5-(2-chloro-1-nitroalkyl)-3-phenyl-and 5-(2-chloro-1-nitroalkyl)-3-methyl-1,2,4-oxadiazoles

3-Phenyl-and 3-methyl-5-(2-chloro-1-nitroalkyl)-1,2,4-oxadiazoles reacted with piperidine, pyrrolidine, and morpholine to give the corresponding 5-(2-amino-1-nitroalkyl) derivatives, while their reactions with sodium p-toluenesulfinate led to the formation of 2-[3-methyl(or phenyl)-1,2,4-oxadiazol-5-yl]-2-nitroethyl p-tolyl sulfones.     

A highly enantioselective synthesis of 5-(l-menthyloxy )-4-substituted-3-chloro-2(5H )-furanones

In this paper, stereocontrolled tandem Michael addition-elimination reaction of the novel chiral source, 5-(l-menthyloxy)-3,4-dichloro-2(5H)-furanone, with various thiols and amines has been investigated. A series of new enantiomerically pure compounds, 5–(l-menthyloxy)-4-substituted-3-chloro-2(5H)-furanones, were obtained in good yields with d. e. ? 98% under mild conditions.     

Synthesis of 3-(2-chloro-5-nitroanilino and 4-nitroanilino)-1-(2,4,6-trichlorophenyl)-2-pyrazolin-5-ones

A new synthesis of 3-anilino-1-aryl-2-pyrazolin-5-ones in which the pyrazolinone ring is built via N? N bond formation is described. 2-Cyano-2′,4′,6′-trichloroacetanilide 1 was converted to imino ether hydrochloride 2 which was reacted with anilines in methanol to produce N-arylimino ether 3a,b. Reaction of these N-arylimino ethers with hydroxylamine gave N-arylamidoximes 4a,b . An 1,2,4-oxadiazol-5-one 6a was prepared from the N-arylamidoxime 4a and subjected to base-induced rearrangement. The desired 3-anilino-pyrazolinone 7a was obtained only in a very low yield. However, O-acetylation of the N-arylamidoximes 4a,b followed by acid-catalyzed ring closure and rearrangement in the presence of excess acetic anhydride gave a mixture of N-acetylanilinopyrazolinones (e.g. 10 ) and 4-acetyloxy-3-N-acetylanilinopyrazoles (e.g. 12 ) which upon acid hydrolysis afforded the 3-anilinopyrazolinones 7a,b in better yield.     

The first enantioselective synthesis of (S)-5-bromo-3-(1-methyl-2-pyrrolidinyl)pyridine: a key intermediate for the preparation of SIB-1508Y

The first enantioselective synthesis of (S)-5-bromo-3-(1-methyl-2-pyrrolidinyl)pyridine is described via intramolecular hydroboration–cycloalkylation of an azido-olefin intermediate. The chiral homoallylic alcohol was efficiently synthesized by enantioselective reduction of the corresponding ketone using (+)-diisopinocamphenylchloroborane as the key reaction. The total synthesis of (S)-SIB-1508Y was achieved with an enantiomeric excess (e.e.) of 94% in ten steps and in 18% overall yield from the commercially available 5-bromo-3-pyridinecarboxylic acid.     

3-溴-1-(3-氯-2-吡啶基)-1H-吡唑-5-甲酸的合成

以2,3-二氯吡啶为起始原料,通过水合肼亲核取代、马来酸二乙酯环合制得2-(3-氯-2-吡啶基)-5-氧-3-吡唑烷甲酸乙酯(5);5经苯磺酰氯酯化、溴化氢溴化制得3-溴-1-(3-氯-2-吡啶基)-4,5-二氢-1H-吡唑-5-甲酸乙酯(7);7经脱氢、水解合成了用于制备氯虫酰胺的关键中间体--3-溴-1-(3-氯-2-吡啶基)-1H-吡唑-5-甲酸,总收率39.5%,其结构经~1H NMR和MS确证.     

3-氯-4-二苄胺基-5-甲氧基-2(5H)-呋喃酮的合成与晶体结构

在THF溶液中合成了标题化合物3-氯-4-二苄胺基-5-甲氧基-2(5H)-呋喃酮,并用FT-IR、UV-Vis、1HNMR、13C NMR、MS、元素分析和X-射线衍射等进行了表征。结果表明此化合物属正交晶系,空间群为Pbca,晶胞参数为:a=15.891(16),b=11.126(11),c=19.778(19),α=β=γ=90°,V=3497(6)3,Z=8,Dc=1.306Mg/m3,μ=0.234 mm-1,F(000)=1440。在化合物的分子结构中,两个苯环几乎垂直于呋喃酮平面,且它们与呋喃酮平面的两面角分别为89.38°和88.19°。     

新型3-氯-1-(3-氯-2-吡啶)-1H-吡唑甲酰胺类化合物的合成

2,3-二氯吡啶肼解后与马来酸二乙酯成环,再经氯代、氧化、水解制得3-氯-1-(3-氯-2-吡啶)-1H-吡唑-5-甲酸(6);6经二氯亚砜酰氯化、环胺酰胺化合成了13个新型3-氯-1-(3-氯-2-吡啶)-1H-吡唑甲酰胺类化合物,其结构经1HNMR和MS表征。     

Synthesis of 2-and 6-chloro-3-(5-methyl-1,3,4-oxadiazol-2-yl)pyridines

A convenient synthesis of 2- and 6-chloro-3-(5-methyl-1,3,4-oxadiazol-2-yl)pyridines, 3 and 10 , utilizing the readily available amide 7 is described. Incorporation of the 3-t-butylamino-2-hydroxypropoxy side chain onto 3 provided 2 , a potential bioisostere of 1 . The antihypertensive activities of 2 and 12 were evaluated in the spontaneously hypertensive rat model.     

Synthesis of Methyl-N-[4-(3-R-amino-2-hydroxypropoxy)phenyl]carbamates

By alkylation of methyl-N-(4-hydroxyphenyl)carbamate with (chloromethyl)oxirane in acetone in the presence of K₂CO₃ methyl-N-[4-(2,3-epoxypropoxy)phenyl]carbamate was prepared. The aminolysis of the latter effected by benzylamine, morpholine, piperidine, and pyrrolidine occurs in keeping with Krasusky rule to afford methyl-N-[4-(3-R-amino-2-hydroxypropoxy)phenyl]carbamates.     

Synthesis and molecular structure of ethyl [N-tosyl-(R)-prolyloxy]-2(S)-[4-cyano-8,8-ethylenedioxy-5-oxo-5,6,7,8-tetrahydroindolizin-3-yl] acetate, a key intermediate in the total synthesis of (20S)-camptothecins

The synthesis of optically active [N-tosyl-(R)-prolyloxy]-2(S)-[4-cyano-8,8-ethylenedioxy-5-oxo-5,6,7,8-tetrahydroindolizin-3-yl] acetate (4a), a key intermediate for the total asymmetric synthesis of 20(S)-camptothecin anticancer drugs, is described. Its structure was characterized by 2D-NMR techniques and the absolute configuration was further confirmed for the first time by X-ray crystal structure analysis.     

新手性源5-(l-孟氧基)-3-溴-2(5H)-呋喃酮的合成和结构

文中深入研究了5-(l-孟氧基)-3-溴-2(5H)-呋喃酮新手性源(5a)的合成方法及其不对称合成反应。5a不仅制备方法简便,光学纯度单一,而且它作为稳定的Michael受体,可与碳、氧、氮、硫等不同的亲核试剂发生串联的Michael加成/分子内亲核取代反应,制备得到含有多个手性中心的双环[3.3.0^3^,^7]-5-辛烯类化合物、双环[3.1.0^3^,^5]-己烷类化合物和螺-环丙烷类化合物。本文报道了该手性呋喃酮5a的合成和构型测定。     

Synthesis and Crystal Structure of Ethoxyethyl 3-(2-chloro-5-pyridyl methylamino)-2-cyano-3-methylthio acrylate

１ＩＮＴＲＯＤＵＣＴＩＯＮＡｍｏｎｇｔｈｅｗｉｄｅｖａｒｉｅｔｙｏｆｐｈｏｔｏｓｙｓｔｅｍＩ（ＰＳＩ）ｐｈｏｔｏｓｙｎｔｈｅｔｉｃｅｌｅｃｔｒｏｎｔｒａｎｓ ｐｏｒｔｉｎｈｉｂｉｔｏｒｓ,ｔｈｅｈｉｇｈｌｙｐｏｔｅｎｔｃｙａｎｏａｃｒｙｌａｔｅＰＳＩ...     

Synthesis of 2-(2-Naphthyl)quinolines from Z-3-(2-Naphthyl)-3-chloro-2-propenal

By reaction of Z-3-(2-naphthyl)-3-chloro-2-propenal and aromatic amines 1-(2-naphthyl)-3-iminoaryl-1-propenylarylamines were prepared which at heating in the glacial acetic acid afforded the corresponding 2-(2-naphthyl)quinolines.     

1,3-双[3-(1-甲氧基-2-羟基丙氧基)丙基]封端聚硅氧烷的合成

以1,3-双[3-(1-甲氧基-2-羟基丙氧基)丙基]四甲基二硅氧烷和八甲基环四硅氧烷(D4)为原料,通过阳离子催化开环聚合制备了1,3-双(3-(1-甲氧基-2-羟基丙氧基)丙基)封端聚硅氧烷,研究了反应温度,反应时间,催化剂种类及加入量对于聚合反应的影响,结果表明,最佳反应条件为:反应温度65℃,反应时间24h,浓硫酸作为催化剂加入量为反应物质量的0.3%,此时反应拥有最高的转化率。通过红外光谱与核磁共振光谱对产物进行了表征。     

New synthetic route to the important (S)-5-(1-(tert-butoxycarbonyl)pyrrolidin-2-yl)-2-methylthiophene-3-carboxylic acid intermediate for the synthesis of a novel glucokinase activator

To obtain an efficient and practical route to a novel glucokinase activator, we investigated a novel synthetic method for the preparation of its key intermediate (S)-5-(1-(tert-butoxycarbonyl)pyrrolidin-2-yl)-2-methylthiophene-3-carboxylic acid through the asymmetric transfer hydrogenation of a pyrroline derivative. The hydrogenation of this pyrroline derivative using the iridium (III)-prolinamide complex Cp*IrCl[(R)-PA] at atmospheric pressure provided an initial intermediate in approximately 50% ee. Further purification via recrystallization provided the desired key intermediate in an excellent enantiopurity, which was applicable to practical use.     

Synthesis of n-(2-chloro-5-bromo-4-pyrimidyl)- and N-(2-chloro-5-iodo-4-pyrimidyl)amino acids

The previously unreported N-(2-chloro-5-bromo-4-pyrimidyl)- and N-(2-chloro-5-iodo-4-pyrimidyl) amino acids were synthesized.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 527–529, April, 1971.