Application of Secondary Amines in the Synthesis of Some New Spiro Heterocyclic Compounds

1-Anilinocycloalkanecarbonitriles 1a–c were prepared and reacted with active methylene reagents to give compounds 5a–c through 10a–c and reacted with different other reagents such as benzaldehyde, ethyl aminoacetate, ethyl mercaptoacetate, or hydrazine carbothioamide, which afforded the desired spiro heterocycles compounds 11a–c through 14a–c.     

Synthesis and QSAR Study of Some Novel Heterocyclic Derivatives as In Vitro Cytotoxic Agents

2,3‐Diaryloxirane‐2,3‐dicarbonitriles have employed in heterocyclic synthesis in many organic reactions. Authors highlight its use as intermediate in the synthesis of various organic compounds through the reaction with different nitrogen nucleophiles as methyl hydrazine, thiourea, thiosemicarbazide, methylglycinate, and others to furnish new heterocyclic derivatives. They are also used as key starting materials to construct some important heterocycles. Structures of all newly synthesized products are substantiated by studying their micro analytical and spectral data. Some of newly synthesized compounds were evaluated for their in vitro cytotoxic effects against a panel of three human tumor cell lines, namely, Hep‐G2, Hela, and MCF‐7. Most of the newly synthesized compounds ( 1a , 2a , 2d , 3 , 4 , 5 , 6a , 6c , 6d , 7a , and 7b ) inhibited cell proliferation with IC₅₀ values in range of 0.52–5.21 μΜ. For activity against HepG2 cell line, compounds 5 , 6a , 6d , and 7b emerged as the most active members. The Hela cell line showed highest sensitivity toward compounds 2a , 2d , and 6c whereas compounds 2d and 6c showed the highest inhibitory activity against MCF‐7 cell line.     

A Novel Synthesis of Fused Heterocyclic Sulfones

The applicability and synthetic potency of the novel reagent diethyl 2‐aryl‐3‐phenylsulfonylpropen‐1,1‐dicarboxylate 3 is reported. Compound 3 proved to be a key precursor in heterocyclic sulfones syntheses. Chemical and spectroscopic evidence for the structure of the newly synthesized compounds are described.     

Triflamides and Triflates of Six-membered Heterocyclic Amines

Reactions of secondary cyclic amines (piperidine, morpholine, thiomorpholine, 1⁶,4-thiazinane-1,1-dione) with trifluoromethanesulfonic anhydride or with N-phenyltriflimide both in the presence and in the absence of a base (Et₃N) result in formation of corresponding triflamides and triflates of the initial amines. The triflates and triflamides can be distinguished by their ¹⁹F and ¹⁵N NMR spectra and the presence in the IR spectra of salts of absorption bands in the region 3270-3000 cm^-1 lacking in the spectra of triflamides.     

新型双稠杂环硫醚化合物的合成与表征

以3-巯基-5-氨基-1,2,4-三唑为原料,设计并合成了4个新型的双稠杂环硫醚类化合物。其结构经元素分析,^1H NMR和MS表征。     

Synthesis and Photochemical Properties of Pd(II) Complexes of Secondary Heterocyclic Amines

Ionic [Pd(LH)₂(ClO₄)₂], neutral (PdL₂) complexes of Pd(II) with hetarylamines derived fromdipyridylamine and benz[c,d]indolylamine were synthesized. The ¹H NMR, IR, and UV spectra of the products were studied. Irradiation of neutral Pd(II) complexes with N-derivatives of benz[c,d]indolylamine results in ligand elimination. Photolysis of a neutral Pd(II) complex with 3,5-dichloro-2,2'-dipyridylamine in solution results in ligand cyclization to give 8-chlorodipyrido[1,2-a:2',3'-d]imidazole.     

Novel Organophosphorus Reagents for the Synthesis of Amines

Abstract:

New organophosphorus equivalents of a² type N-protected amine synthons are presented.     

新型含膦五元杂环类化合物的合成

以1-苯基磷杂环戊烷硼烷络合物为起始原料,经羧基化、酯化、格氏反应以及硅基化反应合成了两个新型的含膦五元杂环化合物——顺式-二[3,5-二-(三氟甲基苯基)](1-苯基磷杂环戊烷-2)-甲醇硼烷络合物和顺式-二[3,5-二-(三氟甲基苯基)](1-苯基磷杂环戊烷-2)-三甲基硅氧甲烷硼烷络合物,其结构经1H NMR,13C NMR,31P NMR和HR-EI-MS表征。     

新型含氮杂环硼-二吡咯亚甲基染料类荧光化合物的合成

以对羟基苯甲醛和2,4-二甲基吡咯为原料,设计并合成了两个新型的8-位苯系取代的硼-二吡咯亚甲基染料类荧光化合物--4,4-二氟-8-[4′-(3-吗啉丙氧基)苯基]-1,3,5,7-四甲基-4-硼-3a,4a-二氮杂-s-引达省和1,4-二{4,4-二氟-8-[4′-(2-乙氧基)苯基]-1,3,5,7-四甲基-4-...     

Synthesis and Evaluation of Antimicrobial Activity of Some Novel Heterocyclic Compounds from 5‐Bromosalicylaldehyde

A novel series of coumarins, thiadiazoles, thiazoles, and pyridines were synthesized via reaction of 5‐bromosalicylaldehyde with different reagents. Thus, 5‐bromosalicylaldehyde 1 was reacted with compounds 2a–d affording iminocoumarins 3a–d , which on hydrolysis with 10% hydrochloric acid, afforded coumarins 4a–d , respectively. On the other hand, reaction of 1 with benzylhydrazinecarbodithioate 5 afforded derivative 6 , which reacted with hydrazonoyl halides 7a–f , afforded 1,3,4‐thiadiazoles 11a–f , respectively. Moreover, thiazoles 15 and 16 were obtained via reaction of 1 with thiocarbohydrazide 13 and hydrazonoyl halides. However, condensation of 2‐acetyl‐5‐bromobenzofuran 17 with benzaldehyde afforded chalcone 18 , which reacted with pyridiniumbromides 19a–c , afforded pyridines 20a–c , respectively. Furthermore, pyridines 21–24 were synthesized from the reaction of chalcone 18 with different active methylene compounds. Reaction of 24 with ethylchloroacetate, chloroacetone, and chloroacetonitrile afforded thienopyridines 26a–c , respectively. The structures of the newly synthesized compounds were established based on their spectral data and elemental analyses. Also, selected newly synthesized compounds were screened for their antimicrobial activity against various microorganisms by disk diffusion method.     

Relationship between Structures and Carcinogenicities of Heterocyclic Amines

IntroductionMore than 2 0 heterocyclic amines( HCAs) havebeen purified since Sugimura found the mutageniccompounds from the pyrolysates of amino acids andproteins and from a variety of cooked meats in1 977[1] .To date,nine HCAs( Fig.1 ) have beentested for carcinogenicity in rats and mice and allhave been shown to be potent carcinogens,induc-ing tumors at multiple organ sites.HCAs have re-ceived widespread attention because they are relat-ed closely to our daily life and people have to ing…     

Controlled Reduction of Carboxamides to Alcohols or Amines by Zinc Hydrides

New protocols for controlled reduction of carboxamides to either alcohols or amines were established using a combination of sodium hydride (NaH) and zinc halides (ZnX₂). Use of a different halide on ZnX₂ dictates the selectivity, wherein the NaH‐ZnI₂ system delivers alcohols and NaH‐ZnCl₂ gives amines. Extensive mechanistic studies by experimental and theoretical approaches imply that polymeric zinc hydride (ZnH₂)_∞ is responsible for alcohol formation, whereas dimeric zinc chloride hydride (H?Zn?Cl)₂ is the key species for the production of amines.     

Synthesis and Anion Recognition of a Novel Heterocyclic Organotin Complex

A novel heterocyclic hexacoordinate organotin(Ⅳ) complex, bis(O-vanillin)-semi ethylenediamino dibenzyltin (VEDBT) was synthesized by the reaction of dibenzyltin dichloride with bis(O-vanillin)-semiethyenediamine, its structure has been characterized by spectral methods.The electrodes using VEDBT as a neutral carrier show high selectivity for salicvlate anions.     

Synthesis and Antitumor Activity of Some New Fused Heterocyclic Compounds

Russian Journal of General Chemistry - Reaction of thiopyrimidine derivative 3 with hydrozonoyl chlorides 4a–4e gives new fused heterocyclic compounds 7a–7e containing triazole ring....     

Reaction of Thioxanthylium Cation with Pharmacophoric Heterocyclic Amines

Russian Journal of Organic Chemistry - Reactions of thioxanthylium tetrafluoroborate with pharmacophoric heterocyclic amines, pyrimidin-2-amine, 4,6-dimethylpyrimidin-2-amine,...     

Amide Synthesis from Alcohols and Amines Catalyzed by Ruthenium N‐Heterocyclic Carbene Complexes

The direct synthesis of amides from alcohols and amines is described with the simultaneous liberation of dihydrogen. The reaction does not require any stoichiometric additives or hydrogen acceptors and is catalyzed by ruthenium N‐heterocyclic carbene complexes. Three different catalyst systems are presented that all employ 1,3‐diisopropylimidazol‐2‐ylidene (IiPr) as the carbene ligand. In addition, potassium tert‐butoxide and a tricycloalkylphosphine are required for the amidation to proceed. In the first system, the active catalyst is generated in situ from [RuCl₂(cod)] (cod=1,5‐cyclooctadiene), 1,3‐diisopropylimidazolium chloride, tricyclopentylphosphonium tetrafluoroborate, and base. The second system uses the complex [RuCl₂(IiPr)(p‐cymene)] together with tricyclohexylphosphine and base, whereas the third system employs the Hoveyda–Grubbs 1st‐generation metathesis catalyst together with 1,3‐diisopropylimidazolium chloride and base. A range of different primary alcohols and amines have been coupled in the presence of the three catalyst systems to afford the corresponding amides in moderate to excellent yields. The best results are obtained with sterically unhindered alcohols and amines. The three catalyst systems do not show any significant differences in reactivity, which indicates that the same catalytically active species is operating. The reaction is believed to proceed by initial dehydrogenation of the primary alcohol to the aldehyde that stays coordinated to ruthenium and is not released into the reaction mixture. Addition of the amine forms the hemiaminal that undergoes dehydrogenation to the amide. A catalytic cycle is proposed with the {(IiPr)Ru^II} species as the catalytically active components.     

Synthesis of Hydroxypyrrolone Carboxamides Employing Selectfluor

Reaction of pyrrole‐2‐carboxamides with Selectfluor in MeCN/water (4:1) affords 2‐hydroxy‐5‐oxopyrrole‐2‐carboxamides in yields of up to 80 %. A variety of sensitive functional groups is tolerated, among them aldehydes and alkynes. The new method also works in the presence of allyl groups and appears to be superior to the use of singlet oxygen. Reaction of the monobrominated dihydropyrrolo[1,2‐a]pyrazinone mukanadin C and its nonbrominated analogue afforded bicyclic hydroxypyrrolones. These compounds are interesting as they constitute a partial structure of the marine natural product oxocyclostylidol.