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1.
Maram R. Al-Dweik Jalal A. Zahra Monther A. Khanfar Mustafa M. El-Abadelah Klaus-Peter Zeller Wolfgang Voelter 《Monatshefte für Chemie / Chemical Monthly》2009,140(2):221-228
Abstract A series of ethyl 2-(substituted)-9-cyclopropyl-4-fluoro-6-oxo-1H-imidazo[4,5-h]quinoline-7-carboxylates has been prepared from ethyl 7,8-diamino-1,4-dihydroquinoline-3-carboxylate via thermally induced
reactions with model alkanoic acids or via microwave-assisted cyclocondensation with some arene carboxaldehydes. Acid-catalysed
hydrolysis of the resulting ester derivatives furnished the corresponding imidazoquinoline-7-carboxylic acids. The structures
of these new acid and ester derivatives are based on microanalytical and spectral (IR, MS, and NMR) data.
Graphical abstract
相似文献
2.
Aleksandra Pa?asz 《Monatshefte für Chemie / Chemical Monthly》2012,38(1):1175-1185
Abstract
Knoevenagel condensation of barbituric acids with aromatic aldehydes containing one or two formyl groups was carried out. 5-Arylidenebarbituric acids underwent smooth hetero-Diels-Alder (HDA) reactions with enol ethers to afford cis and trans diastereoisomers of pyrano[2,3-d]pyrimidine-2,4-diones and 5,5′-(1,4-phenylene)bis[2H-pyrano[2,3-d]pyrimidine-2,4(3H)-dione] derivatives in excellent yields (75–88 %). Syntheses were realized by Knoevenagel condensation and HDA reaction in four different reaction conditions: Knoevenagel condensation in water and Diels-Alder reaction in methylene chloride solution, Knoevenagel condensation in water and Diels-Alder reaction without solvent, three-component one-pot reaction in methylene chloride solution, or three-component one-pot reaction in water. All reactions were carried out without catalyst at room temperature. The reactions of malononitrile with Knoevenagel condensation products of barbituric acids and heteroaromatic aldehydes or terephthalaldehyde were examined and did not provide corresponding pyranopyrimidines. 相似文献3.
Anton V. Tverdokhlebov Alexander P. Andrushko Andrey A. Tolmachev Alexander N. Kostyuk Alexander N. Chernega Eduard B. Rusanov 《Monatshefte für Chemie / Chemical Monthly》2005,15(2):1781-1790
Ethyl [4-oxo-3-(2-oxo-2-arylethyl)thiazolidin-2-ylidene]acetates and [4-oxo-3-(2-oxo-2-arylethyl)thiazolidin-2-ylidene]acetonitriles
were shown to react with substituted benzaldehydes at the endocyclic methylene group leading to the corresponding 5-arylmethylidene
derivatives. Their treatment with DMF · POCl3 complex yielded 3-oxo-5-aroyl-2-arylmethylidene-2,3-dihydropyrrolo[2,1-b]thiazole-7-carboxylic acids ethyl esters and -7-carbonitriles. The structures of the pyrrolothiazoles were confirmed by an
X-ray crystallographic study, which indicated the (Z)-configuration at the arylmethylidene moiety. 相似文献
4.
Aibin Wu Jide Liu Shaoxiong Qin Ping Mei 《Monatshefte für Chemie / Chemical Monthly》2010,21(3):95-99
Abstract
A series of mono and bis-2-(2-(dimethylamino)-ethyl)-5-nitro-1H-benzo[de]isoquinoline-1,3(2H)-diones with different amino side chains, a novel family of antitumor agents, has been designed and synthesized. Their antitumor activity was evaluated against HeLa, A549, P388, HL-60, MCF-7, HCT-8, and A375 cancer cell lines in vitro. Preliminary results showed that most of the derivatives had antitumor activity comparable with that of mitonafide, with IC 50 values of 10−6–10−5 M. More importantly, the derivatives had distinct antitumor selectivity against different cancer cell lines. This work provided a novel class of mitonafide-based lead compounds with improved antitumor selectivity against cancer cell lines for further optimization. 相似文献5.
Starting from the readily available 2-aminobenzhydrols ( 7 ), 3-amino-1,2,4-benzotriazine ( 11 ) and 2-amino-3-pyridinol ( 12 ), novel derivatives of 5-phenyl-5H-imidazo[1,2-a][3,1]benzothiazine-2-carboxylic acid, ethyl ester ( 4 ), imidazo[2,1-c][1,2,4]benzotriazine-2-carboxylic acid, ethyl ester ( 5 ) and 4H-imidazo[2,3-c]pyrido-[2,3-e][1,4]oxazine ( 6 ) were prepared. 相似文献
6.
Amol H. Kategaonkar Vilas B. Labade Pravin V. Shinde Atul H. Kategaonkar Bapurao B. Shingate Murlidhar S. Shingare 《Monatshefte für Chemie / Chemical Monthly》2010,46(6):787-791
Abstract
A series of new tetrazolo[1,5-a]quinoline-4-carbonitrile derivatives were synthesized for the first time via tetrazolo[1,5-a]quinoline derivatives. Elemental analysis, IR, 1H NMR, 13C NMR, and mass spectral data were used to elucidate the structures of all newly synthesized compounds. In vitro antimicrobial activities of synthesized compounds were investigated against Gram-positive Bacillus subtilis, Gram-negative Escherichia coli, and two fungi, Candida albicans and Aspergillus niger, in comparison with standard drugs. Some of the tested compounds showed significant antimicrobial activity. 相似文献7.
Abstract
An effective diastereoselective synthesis of (S)-N,N-diethyl-2-formyl-2-(methoxymethoxy)butanamide and (S)-2-formyl-2-(methoxymethoxy)butanoic acid ethyl ester, which are two key chiral building blocks for the synthesis of 20(S)-camptothecins, has been developed by employing an asymmetric bromolactonization using (R)-proline. The (R) compounds were also synthesized to obtain 20(R)-camptothecin. 相似文献8.
The synthesis of spiro[cyclopropane-1,3′-oxindole]-2-carboxylic acid, including novel 3-(2- and 3-pyridyl)-substituted analogues and the novel cyclopropa[c]quinoline-7b-carboxylic acid and their ester and amide derivatives is described. These syntheses involve diastereoselective cyclopropanation reactions of methyl 2-(2-nitrophenyl)acrylate and (3E)-(pyridin-2-ylmethylene)- and (3E)-(pyridin-3-ylmethylene)-1,3-dihydro-2H-indol-2-one with ethyl (dimethyl sulfuranylidene) acetate (EDSA). The synthesis of methyl cyclopropa[c]quinoline-7b-carboxylate involves a regioselective reductive cyclization of a nitro-diester precursor. The relative stereochemistry of key compounds has been determined by single-crystal X-ray structural analysis. 相似文献
9.
Mohammad Rahimizadeh Mehdi Pordel Mehdi Bakavoli Zahra Bakhtiarpoor Ala Orafaie 《Monatshefte für Chemie / Chemical Monthly》2009,20(2):633-638
Abstract
New imidazo[4,5-a]acridone derivatives were synthesized from the rearrangement of 3H-imidazo[4′,5′:3,4]benzo[c]isoxazoles. New imidazo[4,5-a]acridines were obtained from the reaction of imidazo[4,5-a]acridones in boiling POCl3. All of these compounds exhibited antimicrobial activities comparable to streptomycin as reference drug. 相似文献10.
Ya?ar Dürüst Muhammet Y?ld?r?m Chris F. Fronczek Frank R. Fronczek 《Monatshefte für Chemie / Chemical Monthly》2012,38(2):127-138
Abstract
Eleven novel dihydropyrrolo[3,4-c]pyrazole derivatives were obtained by the reaction of chiral (1R)-N-(1-phenylethyl)maleimide and C,N-aryl-substituted nitrilimines. The reaction afforded the cycloadducts as a regioisomeric mixture which can be separable in some cases. The structure and stereochemistry of cycloadducts were assigned on the basis of infrared (IR), 1H and 13C nuclear magnetic resonance (NMR), mass and X-ray spectra, optical rotation measurements, and CHN analyses. 相似文献11.
Nehal A. Hamdy Hatem A. Abdel-Aziz Ahmad M. Farag Issa M. I. Fakhr 《Monatshefte für Chemie / Chemical Monthly》2007,60(4):1001-1010
3-(3-Methylthiazolo[3,2-a]benzimidazol-2-yl)-3-oxopropionitrile was synthesized by refluxing ethyl 3-methylthiazolo[3,2-a]benzimidazole-2-carboxylate, acetonitrile, and sodium hydride. Treatment of 3-(3-methylthiazolo[3,2-a]benzimidazol-2-yl)-3-oxopropionitrile with phenyl isothiocyanate, in the presence of KOH, furnished the corresponding potassium
salt which was converted into thioacetanilide derivative upon neutralization. The thioacetanilide derivative reacts with α-chloroacetylacetone
and ethyl α-chloroacetoacetate to give the 1,3-thiazole derivatives, while the reaction of the'thioacetanilide derivative
with hydrazonyl chlorides gave 1,3,4-thiadiazole derivatives. On the other hand, 3-(3-methylthiazolo[3,2-a]benzimidazol-2-yl)-3-oxopropionitrile reacted with the diazonium salt of both 3-phenyl-5-amino-(1H)-pyrazole and 5-amino-l,2,4-(1H)-triazole to afford the corresponding hydrazones. The latter hydrazones underwent an intramolecular cyclization upon boiling
in pyridine to give pyrazolo[5,1-c]-1,2,4-triazine and 1,2,4-triazolo[5,1-c]-1,2,4-triazine derivatives. Moreover, the behavior of thiazolo[3,2-a]benzimidazol-3(2H)-one towards phenyl isothiocyanate followed by the reaction with α-chloroketones or hydrazonyl chlorides was investigated.
Some of the latter compounds exhibited moderate effects against some bacterial and fungal species. 相似文献
12.
Nasser R. El-Brollosy Mohamed F. Abdel-Megeed Afaf R. Genady 《Monatshefte für Chemie / Chemical Monthly》2001,14(1):1063-1073
A facile and efficient synthesis of a series of novel 1,2,4-triazolo[5,1-b]quinazolines is described. 2,3-Diaryl-2,3-dihydro-1H-1,2,4-triazolo[5,1-b]quinazolin-9-ones were obtained by reaction of 3-amino-2-arylamino-3H-quinazolin-4-ones with aromatic aldehydes as well as by ring closure of the corresponding anils. Treatment of 3-amino-2-arylamino-3H-quinazolin-4-ones with aromatic carboxylic acids afforded 2,3-diaryl-3H-1,2,4-triazolo[5,1-b]quinazolin-9-ones which could also be synthesized by dehydrogenation of the corresponding dihydro derivatives. Reaction of 3-amino-2-arylamino-3H-quinazolin-4-ones with diethyl malonate and acetylacetone gave 3-aryl-3,9-dihydro-9-oxo-1,2,4-triazolo[5,1-b]quinazolin-2-yl-acetic acid ethyl ester and 3-aryl-2-methyl-3H-1,2,4-triazolo[5,1-b]quinazolin-9-ones, respectively. The latter compounds were also prepared via reaction with acetic anhydride, whereas acetylation with acetic anhydride in the presence of pyridine afforded the acetyl derivatives. 相似文献
13.
Svetlana Markovi? Sonja Stankovi? Slavko Radenkovi? Ivan Gutman 《Monatshefte für Chemie / Chemical Monthly》2009,16(9):153-156
Abstract
Two mechanisms for the isomerization of cyclopenta[fg]aceanthrylene to acefluoranthene were revealed. The first pathway occurs via a cyclobutyl intermediate, whereas the second pathway involves a transition state that contains an sp 3-hybridized carbon atom. Both patterns show that the Stone-Wales rearrangement requires extremely high activation energy and indicate that the isomerization process can occur only under a drastic temperature regime. 相似文献14.
Nehal A. Hamdy Hatem A. Abdel-Aziz Ahmad M. Farag Issa M. I. Fakhr 《Monatshefte für Chemie / Chemical Monthly》2007,138(10):1001-1010
Summary. 3-(3-Methylthiazolo[3,2-a]benzimidazol-2-yl)-3-oxopropionitrile was synthesized by refluxing ethyl 3-methylthiazolo[3,2-a]benzimidazole-2-carboxylate, acetonitrile, and sodium hydride. Treatment of 3-(3-methylthiazolo[3,2-a]benzimidazol-2-yl)-3-oxopropionitrile with phenyl isothiocyanate, in the presence of KOH, furnished the corresponding potassium
salt which was converted into thioacetanilide derivative upon neutralization. The thioacetanilide derivative reacts with α-chloroacetylacetone
and ethyl α-chloroacetoacetate to give the 1,3-thiazole derivatives, while the reaction of the'thioacetanilide derivative
with hydrazonyl chlorides gave 1,3,4-thiadiazole derivatives. On the other hand, 3-(3-methylthiazolo[3,2-a]benzimidazol-2-yl)-3-oxopropionitrile reacted with the diazonium salt of both 3-phenyl-5-amino-(1H)-pyrazole and 5-amino-l,2,4-(1H)-triazole to afford the corresponding hydrazones. The latter hydrazones underwent an intramolecular cyclization upon boiling
in pyridine to give pyrazolo[5,1-c]-1,2,4-triazine and 1,2,4-triazolo[5,1-c]-1,2,4-triazine derivatives. Moreover, the behavior of thiazolo[3,2-a]benzimidazol-3(2H)-one towards phenyl isothiocyanate followed by the reaction with α-chloroketones or hydrazonyl chlorides was investigated.
Some of the latter compounds exhibited moderate effects against some bacterial and fungal species. 相似文献
15.
The Henry reaction between
-glyceraldehyde and ethyl nitroacetate allowed the practical development of a diastereoselective synthesis of 3,4,5-trihydroxy-2-nitropentanoic acid esters, which were reduced to polyoxamic acids, which were used in a new diastereoselective synthesis of 3,4-dihydroxyprolines and new enantioselective syntheses of
-threo-
-norvaline and (2S,3R,4R)-2-amino-3,4-dihydroxytetrahydrofuran-2-carboxylic acid methyl ester. 相似文献
16.
Mino R. Caira Emilian Georgescu Florentina Georgescu Florin Albota Florea Dumitrascu 《Monatshefte für Chemie / Chemical Monthly》2011,62(2):743-748
Abstract
Structural elucidation of the dihydro derivatives obtained as by-products in the classic salt method synthesis of pyrrolo[2,1-a]phthalazines and acetylenic dipolarophiles was achieved by X-ray diffraction analysis of a representative compound. In addition, new pyrrolo[2,1-a]phthalazines were obtained by a one-pot three-component reaction that avoids the formation of the dihydro derivative intermediates. 相似文献17.
Farag A. El-Essawy Ahmed F. Khattab Adel A.-H. Abdel-Rahman 《Monatshefte für Chemie / Chemical Monthly》2007,47(4):777-785
1-Carbethoxymethyl-4,6-dimethyl-1H-[1,2,3]triazolo[4,5-d]pyrimidine-5,7(4H,6H)-dione was synthesized and treated with hydrazine hydrate to give the corresponding hydrazide. The latter hydrazide was treated
either with phenylisothiocyanate or with carbon disulfide/alc. KOH to afford the corresponding thiosemicarbazide and oxadiazole
derivatives. Alkylation of 2-mercapto-1,3,4-oxadiazole with dimethyl sulfate or ethyl chloroacetate gave the corresponding
2-methylthio-, and 2-ethylthioglycolate derivatives. Formation of 1,3,4-thiadiazole, 5-mercapto-1,2,4-triazole, and 1,3,4-oxadiazole
were carried out by treating of the latter thiosemicarbazide with conc. H2SO4, NaOH/HCl, and HgO. Treating of 5-mercapto-1,2,4-triazole with ethyl chloroacetate afforded the thioglycolate ester. Hydrolysis
of the latter with hydrazine hydrate afforded the hydrazide derivatives. Condensation of these hydrazides with monosaccharide
aldoses gave the corresponding sugar hydrazones. The novel compounds were tested for antiviral activity against hepatitis
B virus and showed moderate activities. 相似文献
18.
Milan a
i Mladen Trkovnik Frane a
i Elizabeta Has‐Schn 《Journal of heterocyclic chemistry》2006,43(2):261-266
A number of coumarino[6,7‐d]oxazoles (nitrogen analogs of psoralens) have been synthesized from (7‐hydroxy‐2‐oxo‐2H‐chromen‐4‐yl) acetic acid ethyl ester 1 . The synthetic route began with the nitration of 1 with nitric acid in acetic acid to give (6‐nitro‐7‐hydroxy‐2‐oxo‐2H‐chromen‐4‐yl) acetic acid ethyl ester 2 ; (3,6‐dinitro‐7‐hydroxy‐2‐oxo‐2H‐chromen‐4‐yl) acetic acid ethyl ester 3 and (3,6,8‐trinitro‐7‐hydroxy‐2‐oxo‐2H‐chromen‐4‐yl) acetic acid ethyl ester 4 . The reduction of 2 was accomplished with tin(II) chloride, tin, and concentrated hydrochloric acid in ethanol giving (6‐amino‐7‐hydroxy‐2‐oxo‐2H‐chromen‐4‐yl) acetic acid ethyl ester 5 . After the condensation of aminocoumarin 5 with aromatic aldehyde in glacial acetic acid medium, followed the dehydrocyclization to coumarino[6,7‐d]oxazoles 7a‐k . The intermediate Schiff's bases 6a‐k have been obtained from 5 with aromatic aldehyde in ethanol. Antibacterial and antifungal activities of the compounds have been evaluated. 相似文献
19.
5-Hydroxy-7-alkyl-2-phenyl-7H-pyrrolo[2,3-d]pyrimidine-6-carbonitriles (VIIb-d) and 5-hydroxy-2-phenyl-7H-pyrrolo[2,3-d]pyrimidine-6-carboxylic acid, ethyl ester (VIIa) were prepared from 5-carbethoxy-4-chloro-2-phenylpyrimidine (IV) via 4-[(cyanomethyl)alkylamino[-2-phenyl-5-pyrimidinecarboxylic acid, ethyl esters (Vb-d) and 4-[(carboxymethyl)amino]-2-phenyl-5-pyrimidinecarboxylic acid, diethyl ester (Va), respectively. The hydroxy group of the pyrrolo-[2,3-d]pyrimidines could be methylated, acetylated and tosylated. Hydrolysis of 5-methoxy-7-methyl-2-phenyl-7H-pyrrolo[2,3-d]pyrimidine-6-carbonitrile (IX) afforded the corresponding amide (X). 相似文献
20.
Shunsaku Shiotani Hiroyuki Morita Toshimasa Ishida Yasuko In 《Journal of heterocyclic chemistry》1988,25(4):1205-1213
Reaction of ethyl 3-ethoxycarbonylmethoxyfuropyridine-2-carboxylates 2a-2d with sodium ethoxide afforded 3-ethoxy derivatives 3a-3d which converted to 3-ethoxyfuropyridines 5a-5d by hydrolysis and decarboxylation of the ester group. Vilsmeier reaction of 5a and 5b gave 2-formyl-3-ethoxy derivatives 6a and 6b and 2-formyl-3-chloro derivatives 7a and 7b , while 5c and 5d did not give any formyl compound. Bromination of 3-ethoxyfuropyridines with 1 equivalent mole of bromine gave 2-bromo-3-ethoxyfuropyridines 9a-9d , whereas reaction with 3 equivalents of bromine yielded 2,2-dibromo-3,3-diethoxy-2,3-dihydrofuropyridines ( 10a and 10b ) and/or 2-bromo-3,3-diethoxy-2,3-dihydrofuropyridines 11b , 11c and 11d . Treatment of compounds 5a-5d with n-butyllithium in hexane-tetrahydrofuran at ?70° and subsequent addition of N,N-dimethylformamide yielded 2-formyl derivatives 6a-6d . 相似文献