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1.
报道了取代的邻羟基苯乙酮(1a~1e)经Vilsmeier-Haack反应一步制得3-醛基色酮(2a~2e),2a~2e与取代的芳酰肼(3a~3c)缩合制得15个酰腙类化合物(4a~4o),4a~4o在醋酸酐作用下关环得15个3-(2-苝二唑啉基)-色酮(5a~5o),并通过元素分析,IR,~1H NMR和MS诺数据确证了上述化合物的结构。  相似文献   

2.
用KBH_4,CaCl_2为还原剂使D及L缬氨酸甲酯还原得到光学活性产物R-3-甲基-2-氨基丁醇(2a)及S-3-甲基-2-氨基丁醇(2b)。2a,2b同CS_2在KOH存在下反应得到(R)-4-异丙基四氢噻唑-2-硫酮(3a)及(S)-4-异丙基四氢噻唑-2-硫酮(3b)。肉桂酰氯分别同3a及3b在Et_3N存在下反应得到N-肉桂酰(R)-4-异丙基四氢噻唑-2-硫酮(4a)及N-肉桂酰(S)-4-异丙基四氢噻唑-2-硫酮(4b)。用半经验的量子化学PM3方法研究了反应物和产物的电子结构,得到了产物的最优构型和电荷键序分布以及反应焓变。  相似文献   

3.
在DMF溶剂中,不外加催化剂使邻取代芳香醛(1)与5,5-二甲基-1,3-环己三酮(2)发生缩合和加成反应生成3,3,6,6-四甲基-4a-羟基-9-芳基-1,8二氧化-2,3,4,4a,5,6,7,8,9a-十氢化-1H氧杂蒽(3a~3d)。在同样条件下,邻羟基芳香醛与5,5-二甲基-1,3-环己三酮则发生缩合,加成和脱水反应生成3,3-二甲基-9-(5,5-二甲基-3-羟基-2-环己烯-1-酮-2-基)-1-氧代-2,3,4,9-四氢化-1 氧杂蒽(4a~4b)。用单晶X-射线分析法确定了产物3a和4a的晶体结构。  相似文献   

4.
张自义  杨丰科 《有机化学》1994,14(5):553-557
本文首先用5-(3-吡啶)-2H-四唑乙酰基酰肼与芳酰基异硫氰酸盐反应制备成化合物1-[5-(3-吡啶)-2H-四唑乙酰基]-4-芳酰氨基硫脲化合物1a~j, 然后用冰醋酸回流处理1a~j得到一系列化合物5-[5-(3-吡啶)-2H-四唑亚甲基]-2-芳酰氨基-1,3,4-噻二唑2a~j . 化合物1a~b在强碱介质中首先发生降解, 然后进行环化反应 .  相似文献   

5.
Synthesis and antibacterial activity of 7-[(Z)-2-(2-aminothiazol-4-yl)-2-(3-(3-hydroxy-4-pyridon-1-y l)-3- carboxypropoxyimino)acetamido]-3-(1,2,3-thiadiazol-5-yl)thio methyl-3-cephem-4-carboxylic acid (12a) and its related compounds are described. Compound 12a exhibited excellent antibacterial activity against gram-negative bacteria, including Pseudomonas aeruginosa.  相似文献   

6.
B. Robinson  M.Uppal Zubair 《Tetrahedron》1973,29(10):1429-1432
Fischer indolisation of 2-aminophenyl ethyl ketone phenylhydrazone using glacial acetic acid saturated with hydrogen chloride as catalyst affords 3-methylindolo(l′:2′-3:4)2-methylquinazoline and 2-(2-aminophenyl)-3-methylindole. The latter compound is autoxidised to 2-(2-amino-phenyl)-3-hydroxy-3-methyl-3H-indole, a reaction which is shown to be dependent upon the presence of the primary amino group at the 2-position of the 2-phenyl substituent and which is much slower than the corresponding autoxidation of 2-(2-hydroxyphenyl)-3-methylindole to 3-hydroxy-2-(2-hydroxyphenyl)-3-methyl-3H-indole previously reported.Nitration of isopropyl phenyl ketone occurs preferentially at the ortho- rather than the meta- positions of the benzene nucleus.  相似文献   

7.
异氰酸苯醇和N-[2-(4,6-二甲基)-嘧啶基]-羟胺(5)反应生成1-[2-(4,6-二甲基)-嘧啶基]-1-羟基-3-苯基脲(6)。化合物(6)在三乙胺存在下和氯甲酸乙醇反应生成2-[2-(4,6-二甲基)-嘧啶基]-4-苯基-1,2,4-噁二唑烷-3,5-二酮(1)。  相似文献   

8.
3-(2-, 3- and 4-Pyridyl)-2-methoxythiophenes have been prepared in good yields through the Pd(0)-cat-alyzed coupling of the three isomeric bromopyridines with 3-trimethylstannyl-2-methoxythiophene. This compound was prepared through halogen-metal exchange of 3-bromo-2-methoxythiophene followed by stannylation. 3-Bromo-2-methoxythiophene was prepared by dibromination and α-debromination of 2-methoxythiophen. Most attempts to demethylate 2-methoxy-3-pyridylthiophenes using a large variety of reagents failed, probably due to the instability and high reactivity of the desired 3-pyridyl-2-hydroxythiophene systems. Only 2-methoxy-3-(3-pyridyl)thiophene reacted with boron tribromide to give 3-(3-pyridyl)-3-thiolene-2-one, which only was stable in ether solution at ?20°. The attempted demethylation of 2-methoxy-3-(2-pyridyl)thiophene with trimethylsilane chloride/sodium iodide in refluxing acetonitrile led to a dimer. Demethylation of the 2-methoxy-3-pyridylthiophenes with dibenzyl diselenide and sodium borohydride gave 3-pyridylthiophan-2-ones. A number of other routes to prepare 3-pyridyl-2-hydroxythiophenes were also explored, but none of them gave the desired compounds. On the other hand, the 4-(2-, 3-, and 4-pyridyl)-2-hydroxythiophene systems could easily be prepared by hydrogen peroxide oxidation of the corresponding 4-pyridyl-2-thiopheneboronic esters, which were obtained from 2-bromo-4-pyridylthiophenes by halogen-metal exchange followed by reaction with ethyl borate. The 2-bromo-4-pyridylthiophenes were prepared by dibromination of the known 3-pyridylthiophenes to the 2,5-dibromo derivatives, and removal of the 2-bromine by halogen-metal exchange at ?100°, followed by hydrolysis. The 1H nmr and ir spectroscopic investigations show that these quite stable 2-hydroxythiophene systems exist exclusively in the 4-pyridyl-3-thiolen-2-one forms.  相似文献   

9.
Diastereoselective synthesis of a series of (Z)-1-[3-aryl-2-(phenylsulfanyl)-2-oxiranyl]-1-ethanones was effected from the reaction of (Z)-4-aryl-3-(phenylsulfanyl)-3-buten-2-ones with alkaline hydrogen peroxide in tetrahydrofuran. The stereochemistry of the oxiranes has been deduced from two-dimensional NOESY spectrum.  相似文献   

10.
Molecular glues represent an evolution in drug discovery, however, targeted stabilization of protein complexes remains challenging, owing to a paucity of drug design rules. The functional mapping of hotspots has been critical to protein–protein interaction (PPI) inhibitor research, however, the orthogonal approach to stabilize PPIs has not exploited this information. Utilizing the hub protein 14-3-3 as a case study we demonstrate that functional mapping of hotspots provides a triage map for 14-3-3 molecular glue development. Truncation and mutation studies allowed deconvoluting the energetic contributions of sidechain and backbone interactions of a 14-3-3-binding non-natural peptide. Three central 14-3-3 hotspots were identified and their thermodynamic characteristics profiled. In addition to the phospho-binding pocket; (i) Asn226, (ii) Lys122 and (iii) the hydrophobic patch formed by Leu218, Ile219 and Leu222 were critical for protein complex formation. Exploiting this hotspot information allowed a peptide-based molecular glue that elicits high cooperativity (α = 36) and selectively stabilizes the 14-3-3/ChREBP PPI to be uniquely developed.

The functional mapping of a 14-3-3 protein complex, by means of peptide truncations and point mutations, as an approach to identify critical hotspots regions for 14-3-3 molecular glue drug design.  相似文献   

11.
1,4 - Dimethyl - 2 - nitro - 3 - phenylsulphonylnaphthalene (2) reacts with sodium benzenethiolate in DMSO at 120° to give 1 - methyl - 2 - nitro - 4 - phenylthiomethylnaphthalene (4) [tele-substitution product (TSP) of the phenylsulphonyl group] and 1,4 - dimethyl - 3 - phenylsulphonyl - 2 - phenylthionaphthalene (5) [normal substitution product (NSP) of the nitro group]. The analogous reactions of 2 with sodium 2,4,6- trimethylbenzenethiolate and of 2,3 - bisphenylsulphonyl -1,4 - dimethylnaphthalene (3) with sodium benzenethiolate or aliphatic amines give only TSPs of the phenylsulphonyl group. In the case of the reaction of 2 with aliphatic amines both the possible TSPs (tele-substitution of the phenylsulphonyl or of the nitro group) were isolated in 9:1 relative yield. All the data show that the phenylsulphonyl is a leaving group far better than the nitro in such tele-substitution processes. The mechanism previously proposed to account for the formation of TSPs from 1,4-dimethyl - 2,3 - dinitronaphthalene is strongly supported by the obtained results.  相似文献   

12.
1 INTRODUCTION The triazole derivatives were widely studied because they represent the largest group of modern fungicides and extensively used in both human and veterinary therapy and in agriculture[1~3]. For exam- ple, there are commercially available …  相似文献   

13.
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.  相似文献   

14.
Wittig reactions of 2-furaldehyde (20) [and thiophene-2-carbaldehyde (21)] with (3-guaiazulenylmethyl)triphenylphosphonium bromide (19) in ethanol containing NaOEt at 25 °C for 24 h under argon give (E)-1-(2-furyl)-2-(3-guaiazulenyl)ethylene (22E) and (E)-1-(2-thienyl)-2-(3-guaiazulenyl)ethylene (23E) in 53 and 36% yields. Similarly, Wittig reactions of 3-furaldehyde (29) [and thiophene-3-carbaldehyde (30)] with 19 under the same reaction conditions as for 20 and 21 afford (E)-1-(3-furyl)-2-(3-guaiazulenyl)ethylene (31E) and (E)-1-(3-thienyl)-2-(3-guaiazulenyl)ethylene (32E) in 32 and 46% yields. Molecular structures and characteristic properties as well as preparation of the title E (i.e., one of the geometrical isomers) forms, with a view to comparative study, are reported. Moreover, reactions of those conjugated π-electron systems with TCNE (=tetracyanoethylene) in benzene [and in DMF (=N,N-dimethylformamide)] at 25 °C for 24 h under argon yield unique products, possessing interesting molecular structures, respectively, whose characteristic properties and crystal structures are documented, also.  相似文献   

15.
The enantioselective hydrolysis of (+/-)-4-(1-acetoxyethyl)-N-(cyclohexylcarbamoyl)-benzenesulfona mides 3 with lipase Amano P from Pseudomonas sp. in a water-saturated solvent gave (R)-4-(1-hydroxyethyl)-N-(cyclohexylcarbamoyl)benzenesulfonamide 2 (39%, > 99% ee) and unchanged (S)-3 (50%, 62% ee). On the other hand, enantioselective esterification of (+/-)-2 with lipase Amano P in the presence of vinyl acetate provided (R)-3 (41%, > 99% ee) and unchanged (S)-2 (46%, 78% ee).  相似文献   

16.
Wolff-Kishner reduction of 3-amino-4-(o-chlorobenzoyl)pyridine ( 3 ) afforded 3-amino-4-(o-chlorobenzyl)pyridine ( 5 ), which on subsequent reaction with triethyl orthoformate and then acetyl hydrazide yielded 1-acetyl-2-[N-[4-(o-chlorobenzyl)pyridin-3-yl]formimidoyl]hydrazone ( 7 ). Cyclization of hydrazone 7 gave 3-(3-methyl-4H-1,2,4-triazol-4-yl)-4-(o-chlorobenzyl)pyridine ( 8 ), which on Jones oxidation yielded 3-(3-methyl-4H-1,2,4-triazol-4-yl)-4-(o-chlorobenzyl)pyridine ( 9 ). The Mannick reaction of 3-(3-methyl-4H-l,2,4-triazol-4-yl)-4-(o-chlorobenzyl)pyridine ( 9 ) with aqueous formalin and dimethylamine hydrochloride afforded 3-[3-[(dimethylamino)methyl]-5-methyl-4H-1,2,4-triazol-4-yl]-4-(o-chlorobenzoyl)-pyridine ( 10 ). 3-[3-[(Dimethylamino)methyl]-5-methyl-4H-1,2,4-triazol-4-yl]-4-(o-chlorobenzoyl)pyridine ( 10 ) exhibited good anticonvulsant activity in the subcutaneous pentylenetetrazole anticonvulsant screen indi cating that an appropriately substituted-pyridine ring moiety can serve as a bioisostere of a chlorobenzene ring with respect to anticonvulsant activity.  相似文献   

17.
报道了采用溴氧化3-异丙烯基(艹卓)酚酮和3-肉桂酰基(艹卓)酚酮合成杂环并(艹卓)酮化合物的新方法。3-异丙烯基(艹卓)酚酮5位偶联产物1a~1f和3-肉桂酰基(艹卓)酚酮5位偶联产物3a~3d分别在吡啶介质中与过量溴作用生成5-取代苯偶氮基-7-溴-3-甲基-8-氢环庚并呋喃-8-酮2a~2f和6-取代苯偶氮基-2-苯基-8-溴-4,9-二氢环庚并吡喃-4,9-二酮4a~4d。  相似文献   

18.
3-(Pivaloylamino)- and 3-(acetylamino)-4(3H)-quinazolinones react with alkyllithium reagents to give 1,2-addition products in very good yields. Lithiation takes place with LDA and is regioselective at position 2. The lithium reagents thus obtained react with a variety of electrophiles to give the corresponding substituted derivatives in very good yields. Reactions of the lithium reagents with iodine give oxidatively dimerized cyclic structures. 3-(Pivaloylamino)- and 3-(acetylamino)-2-ethyl-4(3H)-quinazolinones and 3-(pivaloylamino)- and 3-(acetylamino)-2-propyl-4(3H)-quinazolinones are lithiated at the benzylic position with LDA. The lithium reagents so produced also react with a variety of electrophiles to give the corresponding 2-substituted-4(3H)-quinazolinone derivatives in very good yields. However, lithiation of 3-(acylamino)-2-(1-methylethyl)-4(3H)-quinazolinones was unsuccessful, as were lithiations of compounds having a diacetylamino group at position 3. The amide groups have been cleaved in good yield under basic or acidic conditions from some of the products to provide access to the free amino compounds.  相似文献   

19.
The BF(3).Et(2)O-promoted Diels-Alder addition of 1-acetylvinyl RADO(Et)-ate (RADO(Et)-ate = 3-ethyl-2-oxo-6,8-dioxa-3-azabicyclo[3.2.1]octane-7-exo-carboxylate) to 1-(dimethoxymethyl)-2,3,5,6-tetramethylidene-7-oxabicyclo[2.2.1]heptane led to one major monoadduct that added to 1,2-didehydrobenzene and was converted into (-)-4-demethoxy-7-deoxydaunomycinone and (2R)-12-acetoxy-2-acetyl-5-(bromomethyl)-1,2,3,4-tetrahydronaphthacen-2-yl RADO(Et)-ate. The latter compound was used to construct (8R)-8-acetyl-6,8-dihydroxy-11-[[(3'-[(aminopropyl)oxy]-, -4'-[(aminobutyl)oxy], and -5'-[(aminopentyl)oxy]methyl]-7,8,9,10-tetrahydronaphthacene-5,12-dione hydrochloride (-)-8, (-)-9, (-)-10, respectively, as well as (8R)-8-acetyl-6,8-dihydroxy-11- [[[2'-[(3"-aminopropyl)amino]ethyl]oxy]- ((-)-11) and -[[3'-[(3"-aminopropyl)amino]propyl]oxy]methyl]-7,8,9, 10-tetrahydronaphthacene-5,12-dione hydrochloride ((-)-12). (8R)-8-Acetyl-6,8-dihydroxy-11-[[(alpha-L-daunosaminyl)oxy]methyl]-7,8,9,10-tetrahydronaphthacene-5,12-dione hydrochloride ((-)-13), a mimic of idarubicin, was also prepared. Absorbance and fluorescence titration experiments showed (-)-8, (-)-9, and (-)-10 to intercalate calf thymus DNA whereas (-)-11, (-)-12, and (-)-13 did not. The best intercalator was (-)-9 (K(b) = (1.1 +/- 0.1) x 10(5) M(-)(1)) with the [(4'-aminobutyl)oxy]methyl chain. Inhibition of topoisomerase II-induced DNA strand religation was observed for (-)-8 at a concentration of 50 &mgr;M.  相似文献   

20.
Reaction of 3-nitrobenzaldehyde with diethyl oxalacetate in the presence of piperidine acetate and then ammonium acetate/acetic acid gave a moderate yield of tetraethyl 1,4-dihydro-4-(3-nitrophenyl)-2,3,5,6-pyridinetetracarboxylate. This was oxidized with nitric acid to tetraethyl 4-(3-nitrophenyl)-2,3,5,6-pyridinetetracarhoxylate which was hydrolyzed and decarboxylated to give 4-(3-nitrophenyl)pyridine.  相似文献   

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