bluuebunny/crossref_metadata_2025 huggingface dataset:
Dérives de l'imidazo[2,1‐b]thiazole. V. Transposition allylique observée au cours de la synthése d'(imino‐2 alkyl‐3 thiazolinyl‐4) acetates d'ethyle et de (dihydro‐5,6 imidazo[2,1‐b]thiazolyl‐3) acetates d'éthyle
Authors: Robert Jean‐Francois , Panouse Jacques J.
Published: March 2009

Le bromhydrate de (phényl‐6 dihydro‐5,6 imidazo[2,1‐b]thiazolyl‐3) acétate d'éthyle subit une transposition allylique en milieu alcalin pour donner le (phényl‐6 tétrahydro‐2,3,5,6 imidazo[2,1‐b]thiazolylidene‐3) acétate d'éthyle. Celui‐ci présente une double liaison juxtanucléaire qui persiste apres acidification. Les differents (imino‐2 alkyl‐3 thiazolinyl‐4) acetates d'ethyle utilises comme intermidiaires de synthese subissent une transposition analogue sous forme de base. Mais apres acidification il y a retour a une structure thiazolique. Les donnees rmn protoniques sont utilisees pour expliquer ces transpositions sous l'influence du pH, qui font egalement intervenir les contraintes stériques et l'existence de conjugaison π p π.
Unusual formation of an oxetane ring. Molecular and crystal structure of 2a‐acetyl‐3‐(1‐methoxyethylidene)‐5a‐methylcyclopenta[b]oxetan‐4‐one
Authors: Adembri Giorgio , Donati Donato , Lampariello Lucia R. , Scotton Mirella
Published: March 2009

The reaction between 2,3‐diacetyl‐4‐hydroxy‐4‐methylcyclopent‐2‐en‐1‐one, 2, and diazomethane gave a mixture of four compounds, two of which, 5 and 6, resulted to be cyclopenta[b]oxetane derivatives. The structure of 5 was determined by X‐ray analysis. Some aspects of the mechanism are discussed.
Synthesis of α‐carboxy‐γ‐butyrolactones by rearrangement of capto‐dative cyclopropanes on silica surfaces
Authors: Alonso Miguel E. , Gómez Matilde , De Sierraalta Sarah P. , Patricia Jano S.
Published: March 2009

The rearrangement of some cyclopropanes featuring electron‐withdrawing and electron releasing substitu‐ents on vicinal carbons of the trimethylene ring to α‐carboxy‐γ‐lactones upon contact with silica gel at room temperature has been discovered. One or two alkyl ester groups were chosen as electron attractor substitu‐ents while one or two cyclopropyl units were used for the release of electron density. It was observed that the lactone forming process is strongly dependent upon these substituents to the extent that only two ester groups and at least one cyclopropane will confer enough vulnerability to the tetra‐substituted cyclopropane for the rearrangement to take place. A comparative study of the lactonization by means of contact with silica and alkaline hydrolysis was performed and some mechanistic considerations are put forth.
4‐Hydroxycoumarin/2‐hydroxychromone tautomerism: Infrared spectra of 2‐13c and 3‐D labeled 4‐hydroxycoumarin and its anion
Authors: Obaseki Andrew O. , Porter William R. , Trager William F.
Published: March 2009

Bands with primarily v (C=O) and v (C=O) character in the spectra of 4‐hydroxycoumarin and its anion were identified by isotopic substitution with either 13C or deuterium. Two bands of each type were found for spectra of 4‐hydroxycoumarin in solution in chloroform, dioxane, or dimethylsulfoxide, with v (C=O) at 1704–1733 cm−1 and ∼ 1567 cm−1. Two bands, at 1618 and 1559 cm−1, are associated with v (C=C) in the spectrum of crystalline 4‐hydroxycoumarin monohydrate, but only a single v (C=O) band at ∼ 1655 cm−1 was observed. Anhydrous 4‐hydroxycoumarin has v (C=O) bands at ∼ 1700 cm−1 and a shoulder at ∼ 1670 cm−1. The strong band at 1660 cm−1 in the spectrum of 4‐hydroxycommarin anion in dimethylsulfoxide solution is due to a delocalized v (O = C = O) vibration, whereas the band at 1555 cm−1 has partial v (C=C) character and involves C(3) but not C(2), supporting a fully delocalized char structure for the anion. No evidence for the existence of the 2‐hydroxychromone tautomer was found, except in the case of anhydrous 4‐hydroxycoumarin in the solid state.
Thiophene systems. 7. Pyrido[3,2‐b]thieno[3,4‐e][1,4]diazepine derivatives with potential cns activity
Authors: Press Jeffery B. , Hofmann Corris M. , Wiegand Gretchen E. , Safir Sidney R.
Published: March 2009

Pyrido[3,2‐b]thieno[3,4‐e][1,4]diazepines (1a‐d) were synthesized to investigate their potential CNS activity. Synthesis of the desired ring system was effected by condensation of 2,3‐diaminopyridine (3) with methyl tetrahydro‐4‐oxo‐3‐thiophenecarboxylate (4). Structural assignment of the major condensation product 5 was determined by comparison of 1H nmr absorptions of 5 with those of related methyl lactam derivatives 11 and 14. A discussion of the possible mechanism leading to 5 in preference to isomeric lactam 6 is presented. Biological evaluation of 1a‐d revealed no interesting properties.
Studies on pyrazines.7. The synthesis of 5‐chloropyrazinecarboxylic acid
Authors: Sato Nobuhiro , Arai Shinji
Published: March 2009

The titled carboxylic acid (1) was prepared by condensation of 2‐furylglyoxal with aminoacetamide followed by chlorination of the resulting 2‐hydroxy‐5‐(2′‐furyl)pyrazine (2) and permanganate oxidation. The acid was further converted into methyl ester and 5‐hydroxypyrazinecarboxylic acid.
Reissert compound studies. XLIII. The pyrido[2,3‐b]pyrazine reissert compound
Authors: Veeraraghavan S. , Popp F. D.
Published: March 2009

Both pyrido[2,3‐b]pyrazine (5‐azaquinoxaline) and 2,3‐dimethyl‐5‐azaquinoxaline undergo Reissert compound formation across the 5,6‐position.
Unsymmetrically substituted furoxans. VII. A 13C NMR study of a series of isomeric pairs of furoxans and the structure of the two isomeric chloro‐phenyl‐furoxans
Authors: Calvino R. , Fruttero R. , Gasco A. , Mortarini V. , Aime S.
Published: March 2009

The structure of two isomeric chloro(phenyl)furoxans is proposed by comparison of their 13C nmr spectra with those of several unsymmetrically substituted furoxans and related furazans.
Réaction des carbanions maloniques sur le S‐méthyl ϵ‐thiocaprolactime
Authors: Lhommet Gérard , Richaud Marie Geneviève , Maitte Pierre
Published: March 2009

Le S‐méthyl ϵ‐thiocaprolactime réagit avec des composés a methylene actif comme les β‐dicétones, β‐cito‐esters ou quelques malonates. Nous montrons que le S‐méthyl ϵ‐thiocaprolactime est une meilleure forme ac‐tivee de la fonction amide que le O‐méthyl ϵ‐caprolactime.
4‐Hydroxycoumarin/2‐hydroxychromone tautomerism: Infrared spectra of 3‐substituted‐2‐13c‐4‐hydroxycoumarins
Authors: Porter William R. , Trager William F.
Published: March 2009

By isotopic replacement of the carbonyl carbon with 13C, the CO stretching frequency was identified as the highest frequency strongly absorbing band in the 1550–1750 cm−1 region of the infrared spectra of several 3‐substituted 4‐hydroxycoumarins and 3‐substituted 4‐alkoxycoumarins. The compounds selected for study were either known to crystallize as the coumarin tautomeric form by x‐ray diffraction studies or were congeners of such compounds. The carbonyl band varied from 1664 cm−1 in inter‐ or intramolecularly hydrogen bonded derivatives to 1718 cm−1.
Intramolecular acylation of 3‐oxo‐2‐piperidine‐propionic acid derivatives. Synthesis of hexahydro‐2‐oxopyrano[3,2‐b]pyridines
Authors: Bosch Joan , Bonjoch Josep , Serret Isabel
Published: March 2009

The intramolecular acylation of some δ‐keto acids derived from 3‐oxo‐2‐piperidinepropionic acid are described. Bicyclic enol lactones coming from an O‐acylation reaction are obtained in all cases. The regioselec‐tivity of these processes is discussed in terms of the acylating agent and the δ‐keto acid structure. The procedure establishes a convenient synthesis of hexahydro‐2‐oxopyrano[3,2‐b)pyridines.
Synthesis of 4‐alkyl‐4H‐benzo[e]‐ and 4H‐pyrido[2,3‐e]‐1,2,4‐triazin‐3‐one 1‐oxides for potential anticancer activity
Authors: Foye William O. , Kauffman Joel M. , Kim Young Ho
Published: March 2009

Alkylation of the sodium salt of 4H‐benzo[e]‐1,2,4‐triazin‐3‐one 1‐oxide and its 7‐methyl homolog with benzyl bromide and chloromethoxyethyl acetate gave the 4‐substituted products. Alkylation with aceto‐bromoglucose formed the 3‐ether. Alkylation of 4H‐pyrido[2,3‐e]‐1,2,4‐triazin‐3‐one 1‐oxide gave the 4‐substi‐tuted products with both benzyl bromide and acetobromoglucose. Deacetylation of both the tetra‐O‐acetyl‐glucosyl and acetoxyethoxymethyl derivatives was accompolished was accompolished. Antileukemia tests for several of the 4‐alkyl derivatives showed no activity.
Pyridine N‐sulfides. Benzisothiazolo[2,3‐a]pyridinium tetrafluoroborates and benzothiopheno[3,2‐b]pyridines. Novel heterocyclic systems
Authors: Abramovitch Rudolph A. , Inbasekaran Muthiah N. , Miller Adrian L. , Hanna James M.
Published: March 2009

2‐(2‐Mercaptophenyl)pyridines are prepared from the corresponding phenols and oxidized with N‐chloro‐succinimide and silver tetrafluoroborate to benzisothiazolo[2,3‐a]pyridine salts (4). The latter do not rearrange thermally or photochemically to benzothiopheno[3,2‐b)pyridines (19) and are attacked by nucleophiles at sulfur rather than in the pyridine ring, to give the original 2‐(2‐mercaptophenyl)pyridine back in a reaction involving a dismutation. 19 is prepared by rearranging O‐[2‐(3‐bromo‐2‐pyridyl)‐4‐nitrophenyl]dimethylthio‐carbamate to the S‐aryl compound and heating the latter with strong base.
Ring transformation of 6H‐cyclopropa[e]pyrazolo[1,5‐a]pyrimidine. IV (1). Reduction and reaction of 5a‐acetyl‐6a‐ethoxycarbonyl‐5a,6a‐dihydro‐6H‐cyclopropa[e]pyrazolo[1,5‐a]pyrimidine‐3‐carbonitriles with primary amines
Authors: Kurihara Takushi , Nasu Keiko , Tani Tsutomu
Published: March 2009

The reaction of 5a‐acetyl‐6‐ethoxycarbonyl‐5a,6a‐dihydro‐6H‐cyclopropa[e]pyrazolo[1,5‐a]pyrimidine‐3‐carbonitrile (1a) with benzylamine gave ethyl l‐benzyl‐5‐cyano‐8a,9‐dihydro‐2‐methyl‐1H‐pyrrolo[3,4‐e]‐pyrazolo[1,5‐a]pyrimidine‐8a‐carboxylate (2a), in addition to 5‐acetyl‐3‐benzylamino‐1‐(4‐cyanopyrazol‐3‐yl)‐ 2‐pyridone (3). Reaction of 1a with aniline gave ethyl 6‐acetyl‐8‐anilino‐3‐cyano‐7,8‐dihydro‐4H‐pyrazolo‐[1,5‐a][1,3]diazepine‐8‐carboxylate (4), in addition to ethyl 3‐cyano‐7‐methyl‐6‐pyrazolo[1,5‐a]pyrimidine‐acrylate (5). On the other hand, the same reactions of 1b with benzylamine or aniline gave 2b or 8b, respectively.

Though catalytic hydrogenation of 1a over 5% palladium‐carbon proceeded by ring fission of cyclopropane ring to give 9, 1a (or 1b) afforded 4,5‐dihydro derivatives (13 or 15) by catalytic hydrogenation over platinum oxide.

The reactivity of 5‐methoxy‐4,5,5a,6a‐tetrahydro‐6H‐cyclopropa[e]pyrazolo[1,5‐a]pyrimidine (16), which are related analogs of 1a,b, is also described.
Reactions of 3‐acetyltropolone and its methyl ethers with hydroxylamine. Formation of 8H‐cyclohept[d]isoxazol‐8‐one and 8H‐cyclohept[c]isoxazol‐8‐one
Authors: Sudoh Yasunori , Jin Zhong‐Tian , Imafuku Kimiaki , Matsumura Hisashi
Published: March 2009

The reaction of 3‐acetyltropolone (1) with hydroxylamine under the acidic condition gave 3‐methyl‐8H‐cyclohept[d]isoxazol‐8‐one (4) and its oxime (5), and under the neutral condition gave 4 and 3‐acetyltropolone oxime (6). The reaction of 3‐acetyl‐2‐methoxytropone (2a) with hydroxylamine under the acidic condition gave 4, 5, and 4‐methyl‐1H‐2,3‐benzoxazin‐1‐one (7), and under the neutral condition gave 4, 7, 3‐methyl‐8H‐cyclohept[c]isoxazol‐8‐one (8), and its oxime (9). The reaction of 7‐acetyl‐2‐methoxytropone (2b) with hydroxylamine under the acidic condition gave 4 and 5, and under the neutral condition gave 5, 7, and 9.
Studies on simplified ergoline derivatives. A general six‐step synthesis of phenyl‐substituted 4‐methyl‐3,4,4a,5,6,10b‐hexahydrobenzo[f]quinolin‐1‐(2H)‐one analogs
Authors: Salley John J. , Glennon Richard A.
Published: March 2009

This communication outlines the development of a novel, general synthetic route to substituted α‐tetralones 5, their subsequent conversion to the α,β‐unsaturated ketones 11, and an improved, one‐step transformation of 11 to the tricyclic title compounds 1. Thus, substituted derivatives of 1 can be prepared in six steps from simple benzaldehydes, or, in three steps from more readily available α‐tetralones.
The synthesis of chiral dimethyl substituted macrocyclic polyether‐diester ligands
Authors: Jones Brian A. , Bradshaw Jerald S. , Izatt Reed M.
Published: March 2009

A new series of chiral macrocyclic polyether‐diester ligands has been prepared from four chiral dimethyl substituted tetraethylene glycols (15a,b,16,17) and 2,6‐pyridinedicarbonyl chloride (products 5a‐7), diglycolyl chloride (products 8–10), thiadiglycolyl chloride (product 11), 2,5‐furandicarbonyl chloride (product 12), 4‐chloro‐2,6‐pyridinedicarbonyl chloride (product 13), and 4‐methoxy‐2,6‐pyridinedicarbonyl chloride (product 14). The chiral dimethyl substituted tetraethylene glycols (15a‐17) were prepared from ethyl (S)‐lactate.
Synthesis of imidazole derivatives with potential biological activity
Authors: Belgodere E. , Bossio R. , Parrini V. , Pepino R.
Published: March 2009

l‐Alkylaryl‐2‐sulfamoylimidazole‐5‐carboxamides IV, V and VI were prepared starting from methyl l‐alkyl‐aryl‐2‐mercaptoimidazole‐5‐carboxylates I, II and III. Many interesting reaction intermediates such as the l‐alkylaryl‐2‐sulfamoylimidazole‐5‐carboxylic acids (XVII, XX and XXI) were isolated. The structures of all of the compounds were determined by ir and nmr spectroscopy. Diuretic acitivity tests were also carried out on these compounds. In addition, l‐alkylarylimidazole‐5‐carboxamides XXVII, XXVIII and XXIX were also prepared and tested for biological activity.
Potential anticonvulsants. V. The condensation of isatins with C‐acetyl heterocyclic compounds
Authors: Popp F. D.
Published: March 2009

A number of C‐acetyl heterocyclic compounds were condensed with isatin and substituted isatins to give a series of 3‐hydroxy‐3‐substituted oxindoles. The products from 2‐acetylfuran and isatin, 2‐acetylthiophene and isatin, and 2‐acetylpyridine and 1‐methylisatin were active at 100 mg/Kg in the maximal electroshock seizure test.
Preparation of compounds in the new dipyrrolo[3,4‐b:3′,4′‐e]‐pyridine series from 1‐benzylidene‐2,3‐dioxopyrrolidines. A variation of the hantzsch synthesis
Authors: Snyder Carroll A. , Thorn Mark A. , Klijanowicz James E. , Southwick Philip L.
Published: March 2009

Treatment of easily prepared l‐substituted‐4‐benzylidene‐2,3‐dioxopyrrolidines with ammonium formate produces 1,2,4,6,7,8‐hexahydro‐2,6‐disubstituted‐8‐aryldipyrrolo [3,4‐b:3′,4′‐e]pyridine‐3,5‐diones (II), usually in yields of 50 to 60%. Aromatization of the dihydropyridine ring of the hexahydroderivatives II yields corresponding 1,2,6,7‐tetrahydro‐2,6‐disubstituted‐8‐aryldipyrrolo[3,4‐b:3′,4′‐e]pyridine‐3,5‐diones (III). These compounds appear to be the first to incorporate the dipyrrolo[3,4‐b:3′,4′‐e]pyridine ring system.
Influence de la structure sur l'hydrolyse des N‐pyrrolylmethylene‐2 anilines
Authors: Ali‐Bey Aǐcha , Loukil Hasna Fatiha , Gosselin Gilles , Mathieu André , Mesli Abderrezzak
Published: March 2009

L'hydrolyse de la fonction imine d'une famille de bases de Schiff, dérivees du pyrrole aldéhyde‐2 et d'anilines substitutées (X = H, p‐OCH3, p‐OC2H5, p‐CH3, p‐Cl, p‐Br, m‐CN, m‐NO2, p‐NO2), est étudiee dans tout le domaine de pH. Les courbes d'hydrolyse log kobs (mn−1) = f (pH) sont établies, en milieu hydro‐méthanolique tamponné, par polarographie ou ampéiometrie. L'allure des courbes obtenues aux pH > 5 in‐dique que les N‐pyrrolylméthylène‐2 anilines s'hydrotysent selon le mécanisme setenu pour les N‐benzyli‐denes anilines. La stabilité particuliere des produits étudies aux pH < 5 a permis d'obtenir des courbes d'hydrolyse completes en milieu acide. Une excellente corrélation de Hammett (ϱp′ = + 1,73) a pu ětre ainsi établie sur les paliers ou maximums qui apparaissent aux fortes acidités. Cette stabilité est interprétee en considérant l'effet électrodonneur spécifique du noyau pyrrole. L'influence du paramètre structural X sur la morphologie des courbes log kobs = f (pH) et sur le mecanisme de l'hydrolyse de la fonction imine a pu ětre discutée dans tout le domaine de pH.
Synthesis and demethylation of new 5,6,7,8‐tetrahydro‐4,9‐dimethoxy‐1H‐benz[f]indole
Authors: Malesani Giorgio , Ferlin Maria Grazia , Masiero Sergio
Published: March 2009

The title compound 17 was prepared in good yield starting from 5,6,7,8‐tetrahydro‐l‐naphthol (9) by an advantageous synthesis route consisting of eight steps, as indicated in Scheme 2. Demethylation by reflux heating with anhydrous aluminium chloride in dry benzene furnished 4,9‐dihydroxy‐ and 4,9‐dioxo‐5,6,7,8‐tetrahydro‐1H‐benz[f]indoles (compounds 18 and 19, respectively). All new products were identified on the basis of spectral and analytical data.
Studies on the synthesis of heterocyclic compounds. VIII. Action of acyl halides on 2,2‐di‐n‐butyl‐1,3,2‐benzoxathiastannole, 2‐chloro‐1,3,2‐benzoxathiaarsole and ‐stibole
Authors: Anchisi Carlo , Corda Luciana , Fadda Anna , Maccioni Antonio , Podda Gianni
Published: March 2009

The cleavage reaction of some 1,3,2‐benzoxathiastannole, ‐arsole and ‐stibole derivatives with acetyl and benzoyl chloride is described. The reactions were carried out refluxing in benzene or at room temperature. In all cases, the reaction occurs through the initial cleavage of the S‐M linkage with formation of the respective o‐acylthio derivatives. The structure of the prepared compounds was assigned on the basis of their analytical, physical and spectral data.
On the amination of 1,2,4‐triazines by potassium amide in liquid ammonia and by phenyl phosphorodiamidate. A 15n‐study
Authors: Rykowski A. , Van Der Plas H. C.
Published: March 2009

The amination of 5‐R‐ and 6‐R‐3‐X‐1,2,4‐triazines (R = C6H5, t‐C4H9, X = SCH3, SO2CH3, N+ (CH3)3, Cl) by potassium amide in liquid ammonia has been studied. In all reactions the formation of the corresponding 3‐amino‐1,2,4‐triazines takes place; in some reactions by‐products were found: from 5‐phenyl‐ and 5‐t‐butyl‐3‐(methylthio)‐1,2,4‐triazine a ring contracted product i.e. 5‐phenyl and 5‐t‐butyl‐3‐(methylthio)‐1,2,4‐triazole, from 6‐phenyl‐3‐(methylthio)‐1,2,4‐triazine the dimer 3,3′‐bis‐(methylthio)‐6,6′‐bisphenyl‐5,5′‐bi‐1,2,4‐triazine and from 5‐t‐butyl‐3‐(trimethylammonio)‐1,2,4‐triazine chloride compound bis‐(5‐t‐butyl‐1,2,4‐triazin‐3‐yl)‐ amine. Furthermore the conversion of 5‐phenyl‐ and 5‐t‐butyl‐1,2,4‐triazin‐3‐one into the corresponding 3‐amino compound by treatment with phenyl phosphorodiamidate (PPDA) was studied. A 15N study of these aminations showed that nearly all compounds undergo substitution according to both SN(AE) and SN(ANRORC) processes. The contribution of each of the competitive mechanisms to the amination is strongly influenced by the character of the leaving group.
Preparation of 1‐hydroxyethyl‐2‐trideuteriomethyl‐5‐nitroimidazole
Authors: Miyano Masateru , Smith Jeffrey N.
Published: March 2009

The title compound was prepared by two different procedures. The first route starts with acetonitrile‐d3 and goes through 2‐trideuteriomethyl‐5‐nitroimidazole (6) (Scheme I). The second and more convenient process is direct labeling of metronidazole (1) with alkaline ethanol‐d1.
The synthesis of 8‐azidoadenine, a photoaffinity labeling agent
Authors: Marburg S. , Jorn D. , Tolman R. L.
Published: March 2009

The photoaffinity labeling agent, 8‐azidoadenine, was prepared in good yield by hydrolytic cleavage of 8‐azidoadenosine and characterized as a homogeneous compound. Previously reported physical data for this compound was shown to be in accord with mixtures of 8‐azido‐ and 8‐bromoadenine.
1‐Phenyl‐6,7‐disubstituted‐aminopropyl)‐1,2,3,4‐tetrahydroisoquinolines as possible antituberculer agents
Authors: Kumar P. , Dhawan K. N. , Kishor K. , Bhargava K. P. , Satsangi R. K.
Published: March 2009

The Condensation of 3,4‐disubstituted phenylethylamine and benzaldehyde furnished l‐phenyl‐6,7‐disubstituted‐1,2,3,4‐tetrahydroisoquinolines l. which on reaction with 1,3‐dibromopropane gave l‐phenyl‐6,7‐disubstituted‐2‐(3‐bromoprophyl)‐1,2,3,4‐tetrahydroisoquinolines 2. The reaction of 2 with different secondary amines resulted in the synthesis of 3. The compounds 3 were screened for their in vitro antituberculer activity against Mycobacterium smegmatis, and some of them have been found to be total inhibitors of M. Smegmatis
The synthesis of a potential bisintercalating ethidium bromide analog
Authors: Lopp Irene G. , Wilson W. David , Boykin David W.
Published: March 2009

The synthesis of diethyl‐1,3,4,13b‐tetrahydro‐13b‐phenyl‐2H‐pyrimido[1,2‐f]phenanthridine‐7,12‐dicarba‐mate and N,N′‐3,3′[5,5′‐Bis(3,8‐biscarbethoxyamino‐6‐phenyl)phenanthridinium]propylglutarylamide dichloride are reported starting from 3,8‐biscarbethoxyamino‐5‐(3′‐bromopropyl)‐6‐phenylphenanthridinium bromide.
Bromothiophene reactions. II. A novel rearrangement in the zinc and acetic acid reduction
Authors: Alvarez‐Insúa A. S. , Conde S. , Corral C.
Published: March 2009

The elimination of the α‐bromine atoms of the bromothienylethanolamine derivatives 2a,b,c,d with zinc and acetic acid unexpectedly involved a migration of the ethanolamine side chain from the 3 to the 2 position in the thiophene ring. Experiments carried out with simpler analogous compounds 3, 4 and 6 seem to indicate that this rearrangement takes place only in those cases in which the carbon atom of the side chain next to the ring supports an oxygen atom capable of being protonated in the reaction medium. A tentative mechanism is proposed to explain the experimental results.
Sur l'orientation de la nitration des dérivés Bz‐méthoxylés de l'acétyl‐2 benzofuranne
Authors: Bachelet Jean‐Pierre , Clavel Jean‐Marc , Demerseman Pierre , Royer René
Published: March 2009

Les nitrations directes des acétyl‐2 Bz‐méthoxy benzofurannes par l'acide nitrique dans l'anhydride acétique donnent toujours deux dérivés nitrés sur l'homocycle en ortho ou, éventuellement, en para du méthoxyle, en proportions différentes selon les cas. Les éthers obtenus sont aisément déméthylables par le chlorure de pyridinium. On forme ainsi, en particulier, un analogue nitré de l'Euparone.
Synthesis of thiazolotriazepinones
Authors: Peet Norton P. , Sunder Shyam , Barbuch Robert J.
Published: March 2009

The synthesis of 4,5‐dihydro‐7‐phenylthiazolo[2,3‐c][1,2,4]triazepin‐3(2H)‐one (4) from 2‐propenoic acid 2‐(4‐phenyl‐2‐thiazolyl)hydrazide (14), is reported. A synthesis of 4 which was reported earlier by Mahajan, Sondhi and Ralhan (9), from 3‐chloropropanoic acid 2‐(4‐phenyl‐2‐thiazolyl)hydrazide (3), is erroneous. We were able to cyclize 3 to 1‐(4‐phenyl‐2‐thiazolyl)‐3‐pyrazolidinone (5). The cyclizations of 14 to 4 and 3 to 5 are consistent with the Baldwin Rules for Ring Closure.
Reactions of halogenoquinolizinium bromides with diethylamine
Authors: Sanders Georgine M. , van Dijk M. , van der Plas H. C.
Published: March 2009

The reactions of quinolizinium bromide (QB) and its four monobromo derivatives with diethylamine have been investigated. For Br in position 2 or 4, substitution is the main process, whereas for Br in positions 1 and 3 quantitative ring opening is found. The substituted pyridylbutadienes formed by ring opening, are cis‐trans‐butadienes, which isomerize into the all‐trans forms. The steric cours of the ring opening is explained.
Tetracyclic phenothiazines. VII. Electron impact promoted mass spectral fragmentation of some pyrido[3,2,1‐kl]phenothiazines
Authors: Vishwakarma L. C. , Martin A. R.
Published: March 2009

The mass spectral fragmentation pattern of a series of pyrido[3,2,1‐kl]phenothiazines is reported. The major fragments are derived from the breakdown of the pyrido ring and substituents thereon. The 1,2‐/2,3‐unsaturated, unsubstituted and most of the 3‐substituted compounds show the molecular ion as the base peak indicative of their relative stability toward electron impact. The genesis of the base peaks from the molecular ions of the 2,2‐dithiophenyl substituted compounds probably involves a concerted expulsion of a neutral diphenyldisulfide molecule and hydrogen atom transfer from the 1‐position to the 2‐position in the pyrido ring. On the other hand, 2‐thiophenyl substituted molecular ions lead to base peaks involving simultaneous ring opening of the pyrido ring, cleavage of phenylthiomethylene moiety as a radical and contractive ring closure to the pyrrole system. These two mechanisms appear to be diagnostic for distinguishing 2,3‐ versus 2,2‐positional isomers. The McLafferty rearrangement takes place in the 2‐thiophenyl and 2,2‐dithiophenyl substituted compounds. The retro‐Diels‐Alder fragmentation of the pyrido ring occurs in varying degrees depending on the nature of the 2‐ and 3‐ substituents and also the presence or absence of unsaturation in the pyrido ring. In the 2‐thiophenyl‐3‐keto compounds, thiophenyl group participation with 3‐carbonyl carbon and oxygen atoms is observed in the genesis of some interesting ion fragments. The detection of metastable ions in the spectra of 1,2‐dihydro‐2‐thiophenyl‐, 1,2‐dihydro‐2,2‐dithiophenyl‐3‐hydroxy‐, and 1,2‐dihydro‐2,2‐dithiophenyl‐3‐keto‐3H‐pyrido[3,2,1‐kl]phenothiazines; and spectra of 1,2‐dihydro‐3‐methyl‐, 1,2‐dihydro‐2‐carbethoxy‐3‐keto‐ and 1,2‐dihydro‐2‐thiophenyl‐3‐keto‐3H‐pyrido[3,2,1‐kl]pheno‐thiazines at low voltage support major fragmentation pathways.
Synthesis of 1,2:5,6‐Di‐O‐isopropylidene‐3‐O‐[3‐(uracil‐1‐yl)propionoyl]‐α‐D‐glucofuranose and 1,2‐Mono‐O‐isopropylidene‐6‐O‐[3‐(uracil‐1‐yl)propionoyl]‐α‐D‐glucofuranose
Authors: Ouchi Tatsuro , Jokei Satoshi , Chikashita Hidenori
Published: March 2009

1,2:5,6‐Di‐O‐isopropylidene‐3‐O‐[3‐(uracil‐1‐yl)propionoyl]‐α‐D‐glucofuranose and 1,2‐mono‐O‐isopropylidene‐6‐O‐[3‐(uracil‐1‐yl)propionoyl]‐α‐D‐glucofuranose were synthesized.
Reaction of sulfene with heterocyclic N,N‐disubstituted α‐aminomethyleneketones. XI. Synthesis of 1,2‐oxathiino[5,6‐d]‐1‐benzoxepin derivatives
Authors: Menozzi Giulia , Mosti Luisa , Schenone Pietro , Cafaggi Sergio
Published: March 2009

The 1,4‐cycloaddition of sulfene to N,N‐disubstituted (E)‐4‐aminomethylene‐3,4‐dihydro‐1‐benzoxepin‐5(2H)‐ones gave, generally in excellent yield, N,N‐disubstituted 4‐amino‐3,4,5,6‐tetrahydro‐1,2‐oxathiino‐[5,6‐d)‐1‐benzoxepin 2,2‐dioxides, which are derivatives of the new heterocyclic system 1,2‐oxathiino[5,6‐d]‐1‐benzoxepin. This reaction did not occur only with the N,N‐diphenylenaminone.
Synthesis of 1,2,3,4,5,6‐hexahydro‐1,6‐methano‐3‐benzazocine
Authors: Mazzocchi P. H. , Kordoski E. W. , Rosenthal R.
Published: March 2009

The synthesis of the title compound was accomplished in 48% yield in five steps from indene.
Synthesis and some reactions of naphth[1,2‐d]oxazole‐5‐sulfonic acids
Authors: Osman A. M. , Youssef M. S. K. , Atta F. M.
Published: March 2009

Naphth[1,2‐d]oxazole‐5‐sulfonic acid (1) has been prepared by the fusion of 4‐amino‐3‐hydroxynaphthalene‐1‐sulfonic acid with formamide. Interaction of 1 with a number of arenesulfonyl chlorides, aryloxyacetyl chlorides, 1‐naphthyloxyacetyl chloride, and chloroacetyl chloride gave 2‐(arylsulfonyl)‐, 2‐(aryloxyacetyl)‐, 2‐(1‐naphthyloxyacetyl)‐ and 2‐(chloroacetyl)naphth[1,2‐d]oxaxole‐5‐sulfonic acids (2, 3, 4 and 5), respectively. The corresponding sulfonyl chloride of 2 was condensed with amines giving the expected 2‐(arylsulfonyl)‐naphth[1,2‐d]oxazole‐5‐sulfonamides (6). Interaction of 5 with hydrazine gave 2‐hydrazinoacetyl and disubstituted hydrazine derivatives 7 and 8. Condensation of 7 with aromatic aldehydes yielded substituted hydrazonoacetyl derivatives 9. Two moles of 5 react with one mole of hydroquinone in dry acetone in the presence of anhydrous potassium carbonate and potassium iodide gave 1,4‐bis[5‐sulfonaphth[1,2‐d]oxazol‐2‐ylcarbonyl‐methoxy]benzene (10).
An alternative synthesis of tiopinac
Authors: Thurber T. Craig , Prince Anthony , Halpern Otto
Published: March 2009

Tiopinac (1) [6, 11‐dihydro‐11‐oxodibenzo[b,e]thiepin‐3‐acetic acid, (1)] has shown a high degree of antiinflammatory activity and a low incidence of side effects in animals (2). On the basis of these results, Tiopinac was chosen for human evaluation in 1978 (2a).
Preparation of monohalopyrroles
Authors: Aiello Enrico , Dattolo Gaetano , Cirrincione Girolamo , Almerico Anna Maria , D'Asdia Isabella
Published: March 2009

Monobromo‐, monochloro‐ and monoiodopyrroles are obtained in excellent yields by using N‐halosuccinimides in dimethylformamide as halogenating agents.
Pyrido[1′,2′:1,2]pyrimido[5,4‐d]indoles. A new heterocyclic ring system
Authors: Unangst Paul C.
Published: March 2009

The preparation of the novel pyrido[1′,2′:1,2]pyrimido[5,4‐b]indole ring system is described ‐via fusion at 180° of ethyl 3‐amino‐1H‐indole‐2‐carboxylate 8a and several 6‐chloronicotinic acid derivatives. Similar fusion of 8a and thiourea yielded a 2‐mercaptopyrimido[5,4‐b]indole 18.
Arsenic containing heterocycles. II. Confirmation of the structure of benzo[a]‐9‐chlorophenarsazine 12‐chloride by 13C‐NMR spectroscopy and spin‐lattice relaxation time studies: Possible evidence for the contribution of an 75as‐13C mechanism to the relaxation of the arsenic bearing quarternary carbons in the phenarsazine ring system
Authors: Jay Michael , Martin Gary E.
Published: March 2009

The product of the reaction of (3‐chlorophenyl)‐2‐naphthylamine with arsenic trichloride has been confirmed to be benzo(a)‐9‐chlorophenarsazine 12‐chloride by 13C‐nmr spectroscopy and spin‐lattice (T1) relaxation time measurements. A considerable shortening of the spin‐lattice relaxation times of the arsenic bearing quaternary carbons, relative to the calculated relaxation times, was observed. This discrepancy has been interpreted in terms of an 75As‐13C dipolar contribution to quaternary carbon relaxation.
Synthesis and some reactions of hexahydro‐1,2,4‐triazine‐3,6‐dione
Authors: Schwan Thomas J.
Published: March 2009

The synthesis of hexahydro‐1,2,4‐triazine‐3,6‐dione by hydrogenolysis of 1,2‐dibenzylhexahydro‐1,2,4‐triazine‐3,6‐dione is reported. Ring contraction of the former dione to 3‐amino‐2,4‐imidazolidinedione is discussed. The preparation of the 1‐ and 2‐benzyl derivatives of hexahydro‐1,2,4‐triazine‐3,6‐dione and their conversion to the unsubstituted product are also described.
Novel rearrangements of N‐arylpyrrolyl sulphides
Authors: Cheeseman G. W. H. , Hawi A. A.
Published: March 2009

Base treatment of the pyrrolylthioacetate 2 and the pyrrolylthioacetonitrile 4 unexpectedly yielded a pyrrolo[2,1‐b]thiazole 6 and 2‐(α‐cyano‐2‐nitrobenzyl)thiopyrrole (7), respectively.
A novel synthesis of 2‐aryl‐4‐piperidones by mannich cyclization of iminoketals
Authors: Bosch Joan , Rubiralta Mario , Moral Montserrat , Valls Maria
Published: March 2009

2‐Aryl‐4‐piperidones have been synthesized by condensation between an aromatic aldehyde and a β‐aminoketone ethylene ketal, and further cyclization of the resulting iminoketal with dry hydrogen chloride or anhydrous p‐toluensulfonic acid. Alternatively, reaction of the above iminoketals with methyl fluorosulfonate followed by dry hydrogen chloride treatment and acid hydrolysis gives directly N‐methyl‐4‐piperidones. The application of these reactions to the synthesis of some 2‐aryl‐3‐acetylpyrrolidine systems is also described.
Anticonvulsant property of substituted 5‐aryltetrazol‐2‐ylacetylcarbamides
Authors: Jaiswal R. K. , Jaiswal Neelam , Parmar S. S. , James E. C.
Published: March 2009

Eight 1‐(5‐aryltetrazool‐2‐ylacetyl)3‐substituted carbamides were synthesized as possible anticonvulsants. The anticonvulsant activity possessed by these substituted tetrazolylacetylcarbamides was reflected by their ability to provide 10‐50% protection against pentylenetetrazol(1,5‐pentamethylenetetrazol)‐induced convulsions in mice. These substituted tetrazolylacetylcarbamides possessed low monoamine oxidase inhibitory activity, and the degree of enzyme inhibition ranged from 22‐47% at a final concentration of 1 mmole using kynuramine as the substrate.
Electrochemical synthesis of heterocyclic compounds. XII. Anodic oxidation of catechol in the presence of nucleophiles
Authors: Tabaković Ibro , Grujić Zdravko , Bejtović Zlatko
Published: March 2009

The electrochemical synthesis of coumestan derivatives and some related heterocyclic system (2a‐11a) by anodic oxidation of catechol (1) in the presence of various nucleophiles 2‐11 is described. Products were obtained in good yields and purity. The mechanism of oxidation was deduced from voltammetric data and by coulometry at controlled potential.
Activated nitriles in heterocyclic synthesis. A novel synthesis of pyrazolo[1,5‐a]pyrimidines and pyrano[2,3‐c]pyrazoles
Authors: Elfahham Hassan Attia , Abdel‐Galil Fathy Mohamed , Ibraheim Yusria Rizk , Elnagdi Mohamed Hilmy
Published: March 2009

Several new pyrazolo[1,5‐a]pyrimidines and pyrano[2,3‐c]pyrazoles were synthesized viathe reaction of the cinnamonitrile derivatives 1a‐c with 5‐amino‐3‐phenylpyrazole (1), 3‐amino‐2‐pyrazolin‐5‐one (2) and 3‐amino‐1‐phenyl‐2‐pyrazolin‐5‐one (22).
The synthesis of pyridoquinolines with dialkylaminopropylamine side chains
Authors: Molock Frank F. , Boykin David W.
Published: March 2009

Several new pyridoquinolines with dimethylaminopropyl side chain including 4,7‐bis(3′‐dimethylaminopropylamino)‐1,10‐phenanthroline (1), 4,10‐bis(3′‐dimethylaminopropylamino)‐1,7‐phenanthroline (2), 4,10‐bis(3′‐dimethylaminopropylamino)‐6‐methyl‐1,7‐phenanthroline (3), 4,6‐bis(3′‐dimethylaminopropylamino)‐10‐methylpyrido[3,2‐g]quinoline (4) and 4‐(3′‐dimethylaminopropyl)pyrrolo[lmn][4,7]phenanthroline (5) have been prepared. The compounds were prepared by a multi‐step synthesis which begins with Michael type addition of dimethyl acetylenedicarboxylate or diethyl ethoxymethylenemalonate to the appropriate phenylenediamine. The enamines obtained from the Michael addition were cyclized on heating at elevated temperatures to form the corresponding pyridoquinoline‐diester‐diones. The diester‐diones were saponified decarboxylated and converted into dichloropyridoquinolines which on reaction with dimethylaminopropylamine yielded the title compounds.
A one‐step conversion of N‐acylaminoketones into 5‐alkylidene‐3‐pyrrolin‐2‐ones
Authors: Anselmi Cecilia , Camparini Alfredo , Scotton Mirella
Published: March 2009

A simple and efficient one‐pot synthesis of 5‐alkylidene‐3‐pyrrolin‐2‐ones 3a,e‐g from N‐acylaminoketones is described. A mechanism is proposed and it is substantiated by synthethising and converting the proposed intermediates into the pyrrolinones 3a,e‐g.
Reaction of 1,3‐diaryl‐2,3‐dibromo‐1‐propanones with urea in basic and acidic medium. Synthesis of pyrimidine, imidazoline and imidazolidine derivatives
Authors: Dora E. Khalli , Dash Bhabagrahi , Panda C. S.
Published: March 2009

Reaction of 1,3‐diaryl‐2,3‐dibromo‐1‐propanones 1 with urea in basic medium afforded 4,6‐diaryl‐5‐bromo‐5,6‐dihydropyrimidine‐2(1H)‐ones 4. Oxidation of these bromopyrimidines 4 in dimethylsulphoxide gave 4,6‐diaryl‐1,6‐dihydropyrimidine‐2,5‐diones 6, which were further converted to their thione analogues 7. Reaction of 1,3‐diaryl‐2,3‐dibromo‐1‐propanones 1 with urea, phenylurea and sym‐diphenylurea in glacial acetic acid medium gave in appreciable yields 4‐phenyl‐5‐α‐(bromoarylmethyl)imidazolin‐2‐one 8 and 1,3‐diphenyl‐4‐aroyl‐5‐arylimidazolidin‐2‐one 11 respectively.
Studies on the synthesis of heterocyclic compounds. XI. Cleavage of 1,3‐benzodioxoles by magnesium bromide‐acetic anhydride
Authors: Bonsignore Leonardo , Fadda Anna Maria , Loy Giuseppe , Maccioni Antonio , Podda Gianni
Published: March 2009

The cleavage reaction of some 1,3‐benzodioxole derivatives with magnesium bromide and acetic anhydride has been studied. The reactions have been carried out in acetonitrile solution at room temperature. In all of the 1,3‐benzodioxoles studied, the opening of the heterocyclic ring with formation of bromides, alkenes and their corresponding products of hydrolysis have been observed. The competitive electrophilic substitution on the benzene ring was very limited and was insignificant when a large excess of the cleavage reagent was used. The structures of newly prepared compounds have been determined by elemental analysis, spectroscopic data and comparison with authentic samples.
An ESR study of the cation radicals of azodibenzothiazolyls
Authors: Okada Keiichi , Yamauchi Jun , Deguchi Yasuo
Published: March 2009

Methyl and ethyl derivatives of thiobenzothiazole and their quaternary salts were prepared by the sealed glass tube method. Azinodibenzothiazoles were oxidized by lead(IV) acetate, giving cation radical salts with the boron tetrafluoride anion moiety. The well‐resolved esr spectra observed were analyzed by comparing the data with those of a deuteriomethylated radical and with those from the MO calculations. Spin density distribution was consistently determined by computer simulation, including almost the same unpaired electron distribution on the four nitrogen atoms.
Aspects of the preparation of cyclohexenyl‐ and menthenylthioenynes via ring‐opening of thiophenes
Authors: Svensson Arne , Karlsson J. Olle , Hallberg Anders
Published: March 2009

Treatment of 2,5‐dimethyl‐3‐(1‐menthenyl)4‐bromothiophene (IIIa) and 2,5‐dimethyl‐3‐(1‐cyclohexenyl)4‐bromothiophene (IIIb) with butyllithium gave the thiodienynes Va and Vb, respectively, via ring‐opening of the corresponding 3‐lithio derivatives. 2,5‐Dimethyl‐3‐(1‐menthenyl)‐4‐bromothiophene 1,1‐dioxide (IV) gave the sulfone VI under similar conditions. The uv spectra of IIIa‐b, IV, Va‐b and some related compounds have been recorded and compared. The rotational barrier of compound VI was determined.
Dialkyl bicyclic heterocycles with a bridgehead nitrogen as purine analogs possessing significant cardiac inotropic activity
Authors: Okabe Takayuki , Bhooshan Bharat , Novinson Thomas , Hillyard Ira W. , Garner Garland E. , Robins Roland K.
Published: March 2009

A number of 5,7‐dialkyl‐s‐triazolo[1,5‐a]pyrimidines and 5,7‐dialkylpyrazolo[1,5‐a]pyrimidines and related heterocycles containing a bridgehead nitrogen have been prepared and studied as cardiovascular agents in the anesthetized dog. A number of these compounds have exhibited significant inotropic activity with little effect on heart rate. Especially active were 5,7‐dialkyl‐2‐amino or 2‐alkylthio‐s‐triazolo[1,5‐a]pyrimidines. In contrast, highly polar purine analogs in these ring systems compounds such as 5,7‐di‐n‐propyl‐2‐benzylthio‐1,3,4‐thiadiazolo[3,2‐a]pyrimidine bromide 45 containing a charge on the bridgehead nitrogen, were inactive. The detailed structure activity relationship of the dialkyl derivatives of related ring systems are discussed. The presence of certain ring nitrogen atoms are vital to potent in vivo activity, presumably due to specific enzyme binding at these sites. Several of the compounds studied, showed oral activity and are excellent can‐diates for further evaluation in man.
The chemistry of 5‐hydroxy‐6‐(hydroxyalkyl)uracils. Synthesis of spiro[pyrimidine‐4,2′‐pyrano[3,2‐d]pyrimidines]
Authors: Sasson Isaac M. , Gagnier R. Paul , Otter Brian A.
Published: March 2009

Both 5‐acetoxy‐6‐(acetoxymethyl)‐1‐methyluracil 1 and its parent diol 11 are converted into the spiro[pyrimidine‐4,2′‐pyrano[3,2‐d]pyrimidine] 6 when treated, respectively, with hot methanolic pyridine and with one equivalent of acetic anhydride. The formation of 6 can be explained in terms of the generation and dimerization of the reactive 5‐oxo‐6‐methylene pyrimidine 2. The structure of 6 was determined by 13C nmr spectroscopy and by chemical transformations that lead to the pyrimidinylethylhydantoin 9 and the 6,6′‐[1,2‐ethanediyl]bispyrimidine 10. The more complex 5‐hydroxy‐6‐(hydroxyalkyl)uracils represented by the 6,5′‐cyclourid‐ines 17 undergo an analogous dimerization when treated with acetic anhydride to give structures 22a and 22b. Dimer 22a was also prepared via the 5‐phosphate ester 18. The stereochemistry of dimers 22a and 22b, which is apparent from their 1H nmr spectra, indicates that two molecules of the enones 21a or 21b dimerize in a highly stereoselective manner.
Synthesis of some benzopyranocyclopentapyridine and pyranoacridine derivatives
Authors: Merchant J. R. , Martyres Gail , Koshti N. M.
Published: March 2009

Aminocoumarins react with ethyl cyclopentanone‐and ethyl cyclohexanone‐2‐carboxylates to afford intermediates which on thermal cyclisation yield the title compounds.
Some 4‐alkyl s‐triazolo[4,3‐a]quinoxalines
Authors: Campaigne E. , Mclaughlin A. R.
Published: March 2009

A number of higher homologs of 4‐alkyl 2‐triazolo[4,3‐a]quinoxalines, some of which have a methyl or di‐chloromethyl group at position 1, have been prepared and characterized.
Quinazolines and 1,4‐benzodiazepines. XCIV. Pyrazino[1,2‐a][1,4]benzodiazepines
Authors: Walser A. , Flynn T. , Fryer R. I.
Published: March 2009

A series of pyrazino[1,2‐a][1,4]benzodiazepines were prepared by acylating the primary amino group of an α‐amino‐1,4‐benzodiazepine‐2‐ylideneacetic acid ester (1) with α‐chloroacyl chlorides followed by cyclo‐dehydrohalogenation with triethylamine in dimethylformamide. Some pharmacological data for CNS‐activity are discussed.
A template effect in the synthesis of dibenzo‐14‐crown‐4 derivatives
Authors: Chen C. S. , Wang S. J. , Wu S. C.
Published: March 2009

A new series of 4‐substituted derivatives of dibenzo‐14‐crown‐4 including 4‐nitro‐DB14‐crown‐4 (2a), 4‐bromo‐DB14‐crown‐4 (2b), 4‐chloro‐DB14‐crown‐4 (2c) and 4‐formyl‐DB14‐crown‐4 (2d) has been synthesized with and without a lithium cation template. No matter with or without the template, a satisfactory correlation between the nature of the substituent group on the benzene ring and the reaction yield is observed. The larger σ values for the substituent groups gave lower yields.
The sulfenylation of substituted imines
Authors: Seitz David E. , Needham Fang‐Ling
Published: March 2009

Conditions for mono‐ and bissulfenylation of N‐methyl‐3,3‐dimethylpyrrolidine‐2,5‐dione are described and compared to a closely related six‐membered imide, N‐methyl‐3‐ethyl‐3‐phenylpiperidine‐2,6‐dione. The influence of solvent, base and electrophile on product distribution is explored.
Synthesis of some new fluorophenothiazines
Authors: Tambi S. B. , Anand Madhu , Taneja Vineeta , Gupta C. L. , Mital R. L.
Published: March 2009

The synthesis of various 3‐substituted derivatives of 7‐fluorophenothiazin‐3‐ol and their 5‐oxides is described. The ir, uv and mass spectral data are also included.
Synthesis of isonipecotinoyl analogues of aminopterin and folic acid
Authors: Sekikawa Isao , Takahashi Yumiko
Published: March 2009

The preparation of isonipecotinoyl analogues of aminopterin and methotrexate is described. Condensation of diethyl N‐isonipecotinoyl‐L‐glutamate 4 with 2‐amino‐5‐bromomethyl‐3‐cyanopyrazine 5 afforded diethyl N‐(N‐[(2‐amino‐3‐cyanopyrazin‐5‐yl)methyl]isonipecotinoyl)‐L‐glutamate 6. Cyclisation of 6 with guanidine followed by blocking group hydrolysis afforded N‐([N‐(2,4‐diaminopteridin‐6‐yl)methyl]isonipecotinoyl)‐L‐glutamic acid 8. Coupling of N‐(2‐amino‐4(3H)ioxopteridin‐6‐yl]methyl)isonipecotinic acid 11 with diethyl L‐glutamate gave diethyl N‐[(N‐[2‐amino‐4(3H)‐oxopteridin‐6‐yl]methyl)isonipecotinoyl]‐L‐glutamate 12. Blocking group hydrolysis afforded N‐[(N‐[2‐amino‐4(3H)‐oxopteridin‐6‐yl]methyl)isonipecotinoyl]‐L‐glutamic acid 13.
Oxidation reactions of indapamide. A novel route to the indole derivative, N‐(3‐sulfamyl‐4‐chlorobenzamido)‐2‐methylindole
Authors: O'Hare M. J. , Tan E. , Rehm C. , Grebow P. , Loev B. , Neiss E.
Published: March 2009

Indapamide (1) is readily oxidized with mild oxidizing agents to the indole derivative 2. Dehydrogenation of indapamide is a convenient one step synthesis of a complex indole compound.
4‐Alkyl(aryl)‐3‐amino‐1,2,5‐thiadiazole 1,1‐dioxides
Authors: Pietruszkiewicz Adolph M. , Baldwin John J. , Bolhofer William A. , Hoffman Jacob M. , Lumma William C.
Published: March 2009

Two methods have been developed for the synthesis of 3‐amino‐1,2,5‐thiadiazole 1,1‐dioxides; one leads to 4‐alkyl derivatives, the other to 4‐aryl analogs.
Diaminopyridazine aus diaminocyclopropenyliumsalzen und (diazomethyl)‐ verbindungen
Authors: Heydt Heinrich , Eisenbarth Philipp , Feith Karin , Regitz Manfred
Published: March 2009

Diaminocyclopropenyliumsalze (14a,b) reagieren in Dichloromethan mit den phosphorylierten Diazomethanen 15a‐e in Gegenwart von Ethyl‐diisopropylamin bzw. 1,5‐Diazabicyclo[4.3.0]non‐5‐en spezifisch zu den 4,5‐Diaminopyridazinen 16a‐f. Aus dem Salz 14c und den Diazomethylverbindungen 15a,c,d sowie f‐k in Dichlormethan im Beisein der bicyclischen Base bilden sich dagegen die 3,4‐Diaminopyridazine 17a‐i. In mechanistischer Hinsicht ist die Bildung intermediär auftretender (Diazomethyl)cyclopropene (14a,b + 15 → 18) bzw. (14c + 15 → 19) im Sinne der elektrophilen Diazoalkansubstitution zu interpretieren; weder 18, noch 19 lassen sich isolieren, sondern gehen eine rasche [1,5]‐Cyclisierung zu den Betainen 20 bzw. 21 ein, die abschließend durch Öffnung der Brückenbindung zu den Pyridazinen 16 bzw. 17 isomerisieren.
4‐Hydroxy‐6‐methyl‐2‐pyrone (triacetic acid lactone) and its 3‐phenylthiomethyl derivative towards aldehydes in the presence of piperidine
Authors: Moreno‐Mañas M. , Papell E. , Ribas J. , Virgili A. , Pleixats R.
Published: March 2009

Aldehydes react with triacetic acid lactone, 1, in the presence of piperidine to afford the pyrones 3a‐d and 5. The intermediacy of quinone‐methides of type 2a‐e has been postulated, and experimental evidence for their existence has been achieved by generation by thiophenol elimination from 7 and subsequent trapping in Diels‐Alder reactions. Two examples are given in reactivity of 7 at the sluggish C‐5 position.
Synthesis of pyrido[2,3‐d]pyrimidin‐4‐one derivatives
Authors: Monge A. , Martinez‐Merino V. , Fernández‐Alvarez E.
Published: March 2009

This paper describes one‐pot synthesis of 5H‐[1,3]thiazolo[3,2‐a]pyrido[3,2‐e]pyrimidin‐5‐one 4, 5H‐dipyri‐do[1,2‐a:3′,2′‐e]pyrimidin‐5‐one 10 and 5H‐pyrido[3,2‐e]pyrimido[1,2‐a]pyrimidin‐5‐one 15 and some of their derivatives, starting with 2‐chloro‐3‐pyridine carboxilic acid 1. Compounds 4 and 10 reacted with phosphorus pentasulfide to give the respective 5‐thione analogues, 5 from 4 and 11 from 10.

Boiling the 5‐thione derivatives with hydrazine hydrate, the respective 5‐hydrazono derivatives 6 from 5 and 12 from 11 were obtained. The 5‐acetyl hydrazono, 7, and the 5‐isopropylidenehydrazono, 8, derivatives were also prepared from 6, and the 5‐propionylhydrazono derivatives, 13, from 12.

Compound 4 reacted with hydrazine to give an adduct with two molecules of hydrazine and the probable structure 16. Treating this adduct with acetone a monohydrazone 17 was obtained. Boiling a suspension of this adduct in DMF, it gave 6,10‐dihydro‐6H‐pyrido[3′,2′:5,6]pyrimido[2,1‐c][1,2,4]triazin‐5‐one 20.
Synthesis and antitumor evaluation of some 1,3‐disubstituted tetrahydropyrimido[4,5‐c]isoquinolines
Authors: Gangjee Aleem , Ohemeng Kwasi A. , Lin Fu‐Tyan , Katoh Arthur A.
Published: March 2009

Cyclocondensation of 6‐amino‐2,4‐dioxopyrimidine or 2,4,6‐triaminopyrimidine with 1‐cyclohexenecarbox‐aldehyde13afforded regiospecifically, tricyclic, angular 1,3‐disubstituted tetrahydropyrimido[4,5‐c]isoquin‐olines5and6respectively. In addition, 2,4,6‐triaminopyrimidine when condensed with 2‐chloro‐1‐cyclohex‐enecarboxaldehyde14, regiospecifically afforded the angular isomer6. However, the cyclocondensation of 2,6‐diamino‐4‐oxopyrimidine with13was regioselective and afforded a mixture of the linear and angular tetrahydropyrimidoisoquinolines2and4. The growth of leukemia L‐1210 cells in culture were inhibited 50% by6at 9 × 10−8M.Compounds4and5were not significantly active.