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Molecules, Volume 5, Issue 6 (June 2000) – 19 articles , Pages 756-915

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129 KiB  
Article
Synthesis and X-Ray Crystal Structure of the First Pure and Air-Stable Salt of Peroxymonosulphuric Acid: (Ph)4PHSO5
by Sandro Campestrini and Marco Crisma
Molecules 2000, 5(6), 886-894; https://doi.org/10.3390/50600886 - 28 Jun 2000
Cited by 3 | Viewed by 7155
Abstract
In this paper we describe the synthesis of tetraphenylphosphonium peroxymonosulphate, its crystal structure and packing mode. The asymmetric unit accomodates two independent molecules of the monopersulphate anion, which are held together by hydrogen bonds. In the packing mode, rows of such dimers are [...] Read more.
In this paper we describe the synthesis of tetraphenylphosphonium peroxymonosulphate, its crystal structure and packing mode. The asymmetric unit accomodates two independent molecules of the monopersulphate anion, which are held together by hydrogen bonds. In the packing mode, rows of such dimers are surrounded by four rows of tetraphenyl cations. The consequence is that the highly water sensitive HSO5¯ anions are segregated inside hydrophobic channels composed by the lipophilic cations. This circumstance presumably accounts for the exceptional stability of the title compound. Full article
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30 KiB  
Article
Reduction and Preparation of a Phthalimide Derivative from a Furo-heliangolide
by Gil Valdo José Da Silva, Vladimir Constantino Gomes Heleno and Mauricio Gomes Constantino
Molecules 2000, 5(6), 908-915; https://doi.org/10.3390/50600908 - 27 Jun 2000
Cited by 4 | Viewed by 8316
Abstract
Goyazensolide, a biologically active natural product classified as a furoheliangolide, was transformed in a phthalimide derivative that showed an enhanced biological activity against Tripanosoma cruzi. The complex natural product was also reduced with high stereoselectivity by hydrogen/Wilkinson’s catalyst; an epimer of this [...] Read more.
Goyazensolide, a biologically active natural product classified as a furoheliangolide, was transformed in a phthalimide derivative that showed an enhanced biological activity against Tripanosoma cruzi. The complex natural product was also reduced with high stereoselectivity by hydrogen/Wilkinson’s catalyst; an epimer of this product was obtained in the reduction with hydrogen/Pd-C. Full article
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77 KiB  
Article
A Facile Method for the Synthesis of 6-Aryl-1-(3-Chloropropanoyl)-4-[(E)-1-(2-Furyl)Methylidene)]-1,2,3,4-Tetrahydro-3-Pyridazinones and 2-(2-Chloroethyl)-5-[α-Aracyl-β-(2-Furyl)]-(E)-Vinyl-1,3,4-Oxadiazoles
by Abdel-Sattar S. Hamad and Ahmed I. Hashem
Molecules 2000, 5(6), 895-907; https://doi.org/10.3390/50600895 - 27 Jun 2000
Cited by 32 | Viewed by 7268
Abstract
The 6-aryl-1-(3-chloropropanoyl)-4-[(E)-1-(2-furyl)methylidene)]-1,2,3,4-tetrahydro-3-pyridazinones (6a-d) were synthesized by the reaction of acid chloride 3 with α-aracyl(β-2-furyl)acrylic acid hydrazides (2a-d) in a high yield, one pot reaction. On the other hand, 2-(2-chloroethyl)-5-[α-aracyl-β-(2-furyl)]-(E)-vinyl-1,3,4-oxadiazoles (7a-d) were also prepared by cyclodehydration of N1[α-aracyl-β-(2-furyl)acroyl-N2[3-chloro-propanoyl] hydrazine derivatives [...] Read more.
The 6-aryl-1-(3-chloropropanoyl)-4-[(E)-1-(2-furyl)methylidene)]-1,2,3,4-tetrahydro-3-pyridazinones (6a-d) were synthesized by the reaction of acid chloride 3 with α-aracyl(β-2-furyl)acrylic acid hydrazides (2a-d) in a high yield, one pot reaction. On the other hand, 2-(2-chloroethyl)-5-[α-aracyl-β-(2-furyl)]-(E)-vinyl-1,3,4-oxadiazoles (7a-d) were also prepared by cyclodehydration of N1[α-aracyl-β-(2-furyl)acroyl-N2[3-chloro-propanoyl] hydrazine derivatives (4a-d). The proposed structures of the products were confirmed by elemental analysis, spectral data and chemical evidence. Full article
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56 KiB  
Article
Synthesis of Polynuclear Heterocyclic Compounds Derived from Thieno[2,3-d]pyrimidine Derivatives
by A. B.A. El-Gazzar and N. A. Hassan
Molecules 2000, 5(6), 835-850; https://doi.org/10.3390/50600835 - 25 Jun 2000
Cited by 31 | Viewed by 7550
Abstract
Reaction of 2-hydrazino-3-methyl-3,4-dihydrothieno[2,3-d]pyrimidin-4-one derivatives 2a,b with aliphatic acids afforded the thienotriazolopyrimidinone derivatives 3a-d, with nitrous acid yielded tetrazolothienopyrimidinone derivatives 4a,b and with carbon disulphide furnished 3-mercaptothienotriazolopyrimidinone derivatives 5a,b. Also, 2a,b reacted with aldehydes to afford the arylhydrazones 6a-f which cyclized into [...] Read more.
Reaction of 2-hydrazino-3-methyl-3,4-dihydrothieno[2,3-d]pyrimidin-4-one derivatives 2a,b with aliphatic acids afforded the thienotriazolopyrimidinone derivatives 3a-d, with nitrous acid yielded tetrazolothienopyrimidinone derivatives 4a,b and with carbon disulphide furnished 3-mercaptothienotriazolopyrimidinone derivatives 5a,b. Also, 2a,b reacted with aldehydes to afford the arylhydrazones 6a-f which cyclized into thienotriazolopyrimidinone derivatives 7a-f. Furthermore, 2a,b condensed with ethyl acetoacetate and ethyl cyanoacetate to afford 2-(1-pyrazolyl) derivatives 9a,b and 10a,b, respectively. On the other hand, 2-hydrazino derivatives 2a,b condensed with a-halo-ketones to yield thienpyrimidotriazinone derivatives 11a,b and with β-diketones, to form 2-(1-pyrazolyl) derivatives 12a-f. Full article
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36 KiB  
Article
Syntheses of Furo[3,2-e][1,2,4]triazolo[1,5-c]pyrimidines and Furo[2`,3`: 5,6]-pyrimido[3,4-b][2,3-e]indolo[1,2,4]triazine as a New Ring System
by Nasser A. Hassan
Molecules 2000, 5(6), 826-834; https://doi.org/10.3390/50600826 - 24 Jun 2000
Cited by 41 | Viewed by 8174
Abstract
2-Amino-4,5-di-(2-furyl)furan-3-carbonitrile (1) reacted with triethyl orthoacetate to afford the corresponding 2-ethoxyimine derivative (2). The latter compound reacted with phenyl hydrazine, p-fluorobenzylamine and sodium hydrogen sulfide, respectively, to afford the corresponding furo[2,3-d]pyrimidine derivatives (3-5). Compound 1 also reacted with carbon disulfide and phenyl isocyanate [...] Read more.
2-Amino-4,5-di-(2-furyl)furan-3-carbonitrile (1) reacted with triethyl orthoacetate to afford the corresponding 2-ethoxyimine derivative (2). The latter compound reacted with phenyl hydrazine, p-fluorobenzylamine and sodium hydrogen sulfide, respectively, to afford the corresponding furo[2,3-d]pyrimidine derivatives (3-5). Compound 1 also reacted with carbon disulfide and phenyl isocyanate to afford 5,6-di-(2-furyl)-1H-4H-furo[2,3-d]-[1,3-thiazin]-4-imino-2-thione (6) and 5,6-di-(2-furyl)-1H-3H-3-phenylfuro[2,3-d]pyrimidin-4-imine-2-one (7), respectively. Treatment of compound 2 with hydrazine hydrate at 0oC afforded compound 8, while on boiling 5,6-di-(2-furyl)-3H,4H-4-imino-2-methylfuro-[2,3-d]pyrimidin-3-amine (9) was isolated. Treatment of 9 with carbon disulfide, cyanogen bromide, ethyl cyanoacetate, diethyloxalate and triethyl orthoformate gave the corresponding furo[3,2-e][1,2,4]triazolo[1,5-c]pyrimidines (10-14). Reaction of 9 with isatin and N-acetyl isatin gave the condensation products 15 and 16 respectively. Full article
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3 KiB  
Editorial
Guest Editor's Notice
by Nugzar Zh. Mamardashvili
Molecules 2000, 5(6), 756; https://doi.org/10.3390/50600756 - 20 Jun 2000
Viewed by 4010
Abstract
The purpose of this special festschrift section is to honour the 70th birthday of Boris D. Berezin, Doctor of Chemical Sciences, Professor, Full Member of the Natural Science Academy of the Russian Federation and the founder of porphyrin and phthalocyanin coordination chemistry studies [...] Read more.
The purpose of this special festschrift section is to honour the 70th birthday of Boris D. Berezin, Doctor of Chemical Sciences, Professor, Full Member of the Natural Science Academy of the Russian Federation and the founder of porphyrin and phthalocyanin coordination chemistry studies in Russia.[...] Full article
(This article belongs to the Special Issue Porphyrin Chemistry)
45 KiB  
Article
Synthesis and Antimicrobial Activities of Some Novel Quinoxalinone Derivatives
by M. M. Ali, M. M.F. Ismail, M. S.A. El-Gaby, M. A. Zahran and Y. A. Ammar
Molecules 2000, 5(6), 864-873; https://doi.org/10.3390/50600864 - 18 Jun 2000
Cited by 166 | Viewed by 12288
Abstract
Condensation of 4-benzoyl-1,2-phenylenediamine with sodium pyruvate in acetic acid furnished two products which were identified as 6-benzoyl and 7-benzoyl-3-methyl-2(1H)quinoxalinones (1a,b). Fusion of 1a with aromatic aldehydes furnished the styryl derivatives 2a-c. Alkylation of 1a,b with dimethyl sulphate or ethyl chloroacetate produced the N-alkyl [...] Read more.
Condensation of 4-benzoyl-1,2-phenylenediamine with sodium pyruvate in acetic acid furnished two products which were identified as 6-benzoyl and 7-benzoyl-3-methyl-2(1H)quinoxalinones (1a,b). Fusion of 1a with aromatic aldehydes furnished the styryl derivatives 2a-c. Alkylation of 1a,b with dimethyl sulphate or ethyl chloroacetate produced the N-alkyl derivatives 3a,b and 4a,b. Hydrazinolysis of the ester derivative 4a with hydrazine hydrate afforded the hydrazide derivative 5 which underwent condensation with aldehydes to give the corresponding hydrazone derivatives 6a,b. In addition, chlorination of 1a with thionyl chloride afforded the 2-chloro derivative 7 which was subjected to reaction with sodium azide and n-butylamine to yield the corresponding tetrazolo (8) and n-butylamino (9) derivatives, respectively. The structures of the compounds prepared were confirmed by analytical and spectral data. Also, some of the synthesized compounds were screened for antimicrobial activity. Full article
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60 KiB  
Article
Synthetic Analogue of Stilbene Containing an Imidazole Nucleus
by Saika Siddiqui and Ramachandra S. Hosmane
Molecules 2000, 5(6), 856-863; https://doi.org/10.3390/50600856 - 18 Jun 2000
Cited by 2 | Viewed by 7260
Abstract
Synthesis of trans-1,2-bis(4-nitro-1-p-methoxybenzylimidazol-5-yl)ethene (1) as an imidazole analogue of stilbene has been reported. In order to confirm the trans geometry of the product using an UV spectral comparison, a mixture of both trans (1) and cis isomer (3) was also [...] Read more.
Synthesis of trans-1,2-bis(4-nitro-1-p-methoxybenzylimidazol-5-yl)ethene (1) as an imidazole analogue of stilbene has been reported. In order to confirm the trans geometry of the product using an UV spectral comparison, a mixture of both trans (1) and cis isomer (3) was also prepared. The synthesis involved one-step dimerization of the precursor, 4-nitro-1-p-methoxybenzyl-5-methyl-1H-imidazole (2), using N-chlorosuccinimide catalyzed by potassium t-butoxide. Full article
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49 KiB  
Article
A New Synthetic Route to Dihydrobenzopyran Via Tandem Demethylation Cyclisation
by Geetha Gopalakrishnan, Viswanathan Kasinath, N. D. Pradeep Singh, R. Thirumurugan, S. Shanmuga Sundara Raj and G. Shanmugam
Molecules 2000, 5(6), 880-885; https://doi.org/10.3390/50600880 - 16 Jun 2000
Cited by 9 | Viewed by 8899
Abstract
A tandem demethylation-cyclisation reaction resulting in the formation of pyran rings using AlCl3/EtSH reagent under mild reaction conditions is reported. X-ray diffraction studies on the intermediate support the suggested mechanism. Full article
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43 KiB  
Article
Spectral and Solvation Properties of Some Dipyrromethene Hydrobromides and Their Oxa- and Thia- Analoges
by Michail B. Berezin, Olga M. Chernova, Pavel A. Shatunov, Natalia A. Pashanova, Dmitri B. Berezin and Aleksandr S. Semeikin
Molecules 2000, 5(6), 809-815; https://doi.org/10.3390/50600809 - 12 Jun 2000
Cited by 6 | Viewed by 6458
Abstract
The spectral and solvatation properties of hydrobromides of 3,3/,4,4/,5,5/-hexamethyldipyrromethene-2,2/, 3,3/,4,4/,5/-pentamethyldipyrromethene-2,2/,3,3/,4/,5,5/-pentamethyldipyrromethene-2,2/, 1/,3,4,5-tetramethyldipyrromethene-2,2/, 3,4,5-trimethyldipyrromethene-2,2/ and their oxa- and thia- analoges in benzene, n-propanol, chloroform, pyridine and N,N-dimethylformamide have been studied. The changes of relative solvation enthalpies are calculated and discussed. Full article
(This article belongs to the Special Issue Porphyrin Chemistry)
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97 KiB  
Article
Structure-Stability Relationships of Phthalocyanine Copper Complexes
by T. N. Sokolova, T. N. Lomova, M. E. Klueva, E. E. Suslova, V. E. Mayzlish and G. P. Shaposhnikov
Molecules 2000, 5(6), 775-785; https://doi.org/10.3390/50600775 - 12 Jun 2000
Cited by 12 | Viewed by 8024
Abstract
The influence of NO2, Br, and COOH function substituents in various positions of Cu(II)Pc on the reactivity of the latter concerning the dissociation of the metal - nitrogen bonds in proton donor solvents is discussed. Full article
(This article belongs to the Special Issue Porphyrin Chemistry)
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383 KiB  
Article
Electrochemical and Electrocatalytical Properties of 3,7,13,17-Tetramethyl-2,8,12,18-Tetrabutylporphyrin in Alkaline Solution
by Egor G. Girichev, Michail I. Bazanov, Nugzar Zh. Mamardashvili and A. Gjeyzak
Molecules 2000, 5(6), 767-774; https://doi.org/10.3390/50600767 - 12 Jun 2000
Cited by 6 | Viewed by 7145
Abstract
The reduction and oxidation behaviour in alkaline solution of 3,7,13,17-tetramethyl-2,8,12,18-tetrabutylporphyrin (L) has been studied by cyclic voltammetry. The shape of I-E curves was investigated at different terminal values of electrode potential and at different scan rates. It was shown that it is possible [...] Read more.
The reduction and oxidation behaviour in alkaline solution of 3,7,13,17-tetramethyl-2,8,12,18-tetrabutylporphyrin (L) has been studied by cyclic voltammetry. The shape of I-E curves was investigated at different terminal values of electrode potential and at different scan rates. It was shown that it is possible to obtain two reversible one-electron electroreduction processes accompanied by the formation of mono- and dianion forms of the porphyrin under specific experimental conditions. The reduction potentials of the L↔L- and L-↔L2- processes are –0.67±0.02 V and –1.12±0.02 V, respectively. Full article
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53 KiB  
Article
Synthesis of Sultam Derivatives with Expected Biological Activity. 15
by S. H. Doss, V. B. Baghos, A. O. Abdelhamid and M. M.A. Halim
Molecules 2000, 5(6), 816-825; https://doi.org/10.3390/50600816 - 10 Jun 2000
Cited by 11 | Viewed by 7851
Abstract
4-(Trihydro-2H-1,2-thiazole-1,1-dioxide-2-yl)benzophenone (1), 4-(3,5-dimethyl-1`,2`-thiazine-1`,1`-dioxide-2-yl)benzophenone (2), and 4-(tetrahydro-2H-1,2-thiazine-1,1-dioxide-2-yl)benzophenone (6) were obtained from 4-aminobenzophenone and the appropriate reagents. Isomeric (E-) and (Z-) 2-Ethoxycarbonyl-4-phenyl-4-(4-tetrahydro-1,2-thiazine-1,1-dioxide-2-yl)phenyl-3-butenoic acids (11 and 12) and 2-carboxy-4(N-phenylthiocarbamoyl)-1-phenyl-6-(tetrahydro-2H-1,2-thiazine-1,1-dioxide-2-yl)naphthalene (16) were also synthesized. Full article
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141 KiB  
Article
The Prognostication of Columnar Mesophases - Synthesis and Mesomorphism of Some Porphyrin Derivatives
by Olga B. Akopova and Sergei A. Zdanovich
Molecules 2000, 5(6), 797-808; https://doi.org/10.3390/50600797 - 10 Jun 2000
Cited by 1 | Viewed by 6630
Abstract
The existence of columnar mesophases (CM) for a new series of the porphyrin derivatives is predicted. With this purpose, the computation of molecular parameters (K, Кc, Кs, Kp, Mm, Mr) is [...] Read more.
The existence of columnar mesophases (CM) for a new series of the porphyrin derivatives is predicted. With this purpose, the computation of molecular parameters (K, Кc, Кs, Kp, Mm, Mr) is carried out for eighty five molecules, including materials with a small number of peripheral substitutes. For verification of the existence of CM in the series of materials examined, some of them are synthesized and their mesomorphism is investigated. Full article
(This article belongs to the Special Issue Porphyrin Chemistry)
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30 KiB  
Article
Spiro Cyclohexadienones from the Reaction of Phenolic Enaminone Derivatives with Hypervalent Iodine Reagents
by Anna Asmanidou, Ioannis Papoutsis, Spyros Spyroudis and Anastasios Varvoglis
Molecules 2000, 5(6), 874-879; https://doi.org/10.3390/50600874 - 9 Jun 2000
Cited by 9 | Viewed by 7074
Abstract
Phenolic enamino compounds, prepared from 2-(4-hydroxyphenyl)-ethylamine and the corresponding β-keto carbonyl compounds, afford spiro cyclohexadienone derivatives on reaction with hypervalent iodine reagents. Full article
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20 KiB  
Article
Moisture Stable Ambient Temperature Ionic Liquids: Solvents for the New Millennium. 1. The Heck Reaction
by Joshua Howarth and Andrea Dallas
Molecules 2000, 5(6), 851-855; https://doi.org/10.3390/50600851 - 9 Jun 2000
Cited by 40 | Viewed by 7414
Abstract
In this paper we report examples of the Heck reaction in the new moisture stable ambient temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF6). We have found that the yield of product is comparable with Heck reactions carried out in DMF, the conventional [...] Read more.
In this paper we report examples of the Heck reaction in the new moisture stable ambient temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF6). We have found that the yield of product is comparable with Heck reactions carried out in DMF, the conventional solvent for this reaction, and that the ionic liquid/catalyst mixture can be recycled several times. Full article
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103 KiB  
Article
Influence of the Nature of Porphyrin and Extraligand on the Stability of Zinc Extracomplexes
by Svetlana V. Zaitzeva, Sergey A. Zdanovich, Tatiana A. Ageeva, Alexandr S. Ocheretovi and Oleg A. Golubchikov
Molecules 2000, 5(6), 786-796; https://doi.org/10.3390/50600786 - 9 Jun 2000
Cited by 12 | Viewed by 6386
Abstract
The mutual influence of ligands within the structure of Zn-porphyrins on the thermodynamic stability of the latter was investigated. Full article
(This article belongs to the Special Issue Porphyrin Chemistry)
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42 KiB  
Article
Synthesis and Spectral Properties of ms-Tetrasubstituted b-Octaalkylporphyrins
by Nugzar Zh. Mamardashvili and Oleg A. Golubchikov
Molecules 2000, 5(6), 757-761; https://doi.org/10.3390/50600757 - 8 Jun 2000
Cited by 2 | Viewed by 5349
Abstract
Four new ms-tetrasubstituted β-octaalkylporphyrins are synthesized and their spectral properties are discussed. Full article
(This article belongs to the Special Issue Porphyrin Chemistry)
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53 KiB  
Article
Solubility of Alkylporphyrins
by Galina M. Mamardashvili, Nugdzar Zh. Mamardashvili and Boris D. Berezin
Molecules 2000, 5(6), 762-766; https://doi.org/10.3390/50600762 - 7 Jun 2000
Cited by 7 | Viewed by 8270
Abstract
The solubility in benzene and ethanol of 2,8,12,18-tetramethyl-3,7,13,17-tetrabuthylporphyrin with various substituents in the5,15-positions of the molecule is investigated. A comparative analysis of the influence of alkyl substituents on porphyrin solubility is carried out. Full article
(This article belongs to the Special Issue Porphyrin Chemistry)
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