bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the synthesis of 3(5)‐carbomethoxy‐4‐hetarylpyrazoles
Authors: Cativiela Carlos , De Villegas Maria D. Diaz , Mayoral José A. , Avenoza Alberto , Roy Miguel A. 
Published: April 2009

Abstract3(5)‐Carbomethoxy‐4‐hetarylpyrazoles 3 can be obtained by the aromatization of the corresponding cis‐3‐benzamido‐3‐carbomethoxy‐4‐hetaryl‐Δ1‐pyrazolines 2 obtained by 1,3‐dipolar cycloaddition of diazo‐methane with methyl Z‐2‐benzamido‐3‐hetarylpropenoates 1. An explanation, based on FMO theory, for the different reactivity of the dipolarophiles with diazomethane is given.
Synthesis of benzo‐halogenated 4‐hydroxy‐2(1H)‐quinolones
Authors: Kappe Thomas , Karem Abdel S. , Stadlbauer Wolfgang 
Published: April 2009

AbstractMalondianilides 3 derived from dichloro substituted anilines 2 undergo cyclization to afford 4‐hydroxy‐2(1H)‐quinolones 4 in very good yields using methane sulfonic acid‐phosphorus pentoxide as catalyst. 3,4‐Dichloro anilines 5 can be shown to yield two isomers, 7 and 8, whereas 3‐substituted anilines 9 afford merely 7‐substituted 4‐hydroxy‐2(1H)‐quinolones 11.
Acid catalyzed hydrolysis of brotizolam, a thienotriazolodiazepine: Spectroscopic study
Authors: Gallo B. , Alonso R. M. , Lete E. , Badía M. D. , Patriarche G. J. , Gelbcke M. 
Published: April 2009

AbstractThe acid catalyzed hydrolysis of the thienotriazolodiazepine, Brotizolam, 2‐bromo‐4‐(2‐chlorophenyl)‐9‐methyl‐6H‐thieno[3,2‐f][1,2,4]triazolo[4,3‐a][1,4]diazepine (1), has been studied spectrometrically (ir, pmr, cmr, and ms). The cleavage reaction of the azomethine bond is reversible and the open‐ring compound is in equilibrium with the ring closed compound (protonated form of the parent drug).
A novel synthesis of precocenes. Efficient synthesis and regioselective O‐alkylation of dihydroxy‐2,2‐dimethyl‐4‐chromanones
Authors: Timár Tibor , Jászberényi J. Csaba 
Published: April 2009

AbstractThe reactions of trihydroxybenzenes 1a‐c and 3‐methylbut‐2‐enoic acid (2) in a zinc chloride/water/phosphoryl chloride system afford either the new trihydroxyphenylbutenone derivatives 3b,c or dihydroxy‐2,2‐dimethyl‐4‐chromanones 4a‐c in good yields. Compounds 3b,c can be cyclized in high yields to 4b,c in 5% sodium hydroxide solution. Regioselective O‐alkylation of 4a‐c leads to 5a‐f in good yields. O‐Alkylation of 5a‐f, followed by reduction and dehydration, results in the formation of precocene 3 (7d) and its regioisomer 7a‐c,e,f. Methylation of 4a‐c gives 6g‐i. Subsequent reduction and dehydration affords precocene 2 (7h) and its regioisomers 7g,i.
Photophysical properties of a C6 hydrocarbon linked porphyrin dimer
Authors: Kozyrev Andrei N. , Mironov Andrei F. , Davila Jorge , Harriman Anthony 
Published: April 2009

AbstractThe synthesis and characterisation of a C6 hydrocarbon linked porphyrin dimer and its zinc complex is described. From fluorescence quantum yields and excited singlet and triplet state lifetimes, recorded for the dimers and the corresponding monomer species, it is suggested that the dimeric porphyrins exist in solution in open and closed conformations. The open conformations retain photophysical properties similar to those of the relevant monomeric species but the closed conformations do not fluoresce.
Synthesis and spectra of 7‐(o‐ and p‐R‐phenyl)‐10,10‐dimethyl‐8,9,10,11‐tetrahydrobenz[c]acridin‐8‐ones. Structure correction of 1,2,3,4‐tetrahydro‐2,2‐dimethyl‐5‐aryl‐6‐aza‐7,8‐benzophenanthren‐4‐ones
Authors: Cortés Eduardo , Martínez Roberto , Avila J. Gustavo , Toscano R. Alfredo 
Published: April 2009

AbstractIt has been reported that dimedone added to α‐arylidennaphthylamines in ethanol with formation of 1,4‐addition products derivatives of 5‐aryl‐5,6,7,8,9,10‐hexahydrobenzo[c]phenanthridin‐7‐ones, III, which are easily oxidized by chromic anhydride to the corresponding tetrahydro derivatives, IV. However, the attempted preparation of these compounds resulted instead of the formation of isomeric acridin‐8‐ones V and VI. Structures were confirmed by ir, 1H nmr, ms and X‐ray spectroscopy.
Some novel quinone‐type dyes containing naphthoquinone and related fused ring systems
Authors: Katritzky Alan R. , Fan Wei‐Qiang 
Published: April 2009

AbstractA variety of 1,4‐thiazines, thiazoles, 1,4‐dithines and 2,2′‐bithiazoles containing fused naphthoquinone and related rings have been prepared. The compounds include several novel chromophoric heterocyclic system and their visible absorption spectra are discussed.
4(5)‐vinylimidazole by dehydrobromination of 1‐triphenylmethyl‐4‐(2‐bromoethyl)imidazole
Authors: Altman Janina , Wilchek Meir 
Published: April 2009

Abstract1‐Triphenylmethyl‐4‐(2‐bromoethyl)imidazole undergoes elimination upon basic treatment providing an easy approach to 4(5)‐vinylimidazole whereas the N‐unsubstituted analogue leads only to substitution products.
Synthesis of 4,12‐dihydro‐4‐oxoquino‐[1,8a,8‐a,b]quinoxaline‐5‐carboxylic acid derivatives
Authors: Chu Daniel T. W. , Maleczka Robert E. , Nordeen Carl W. 
Published: April 2009

AbstractThe synthesis and antibacterial activity of 1‐substituted amino‐2‐fluoro‐4,12‐dihydro‐4‐oxoquino[1,8a,8‐a,b]quinoxaline‐5‐carboxylic acid derivatives are described. The synthetic route includes a carbon homologation and two intramolecular nucleophilic displacement cyclization reactions leading to the novel 4,12‐dihydro‐4‐oxoquino[1,8a,8‐a,b]quinoxaline‐5‐carboxylic acid heterocycle.
Condensed heterocycles containing the pyrimidine nucleus
Authors: Santagati Andrea , Santagati Maria , Russo Filippo , Ronsisvalle Giuseppe 
Published: April 2009

AbstractContinuing earlier studies designed to obtain derivatives of 1,3,4‐thiadiazolo[3,2‐a]pyrimidin‐5‐one and of the isomeric 7‐one of pharmacological interest, some novel compounds 2 and derivatives of 6,7,8,9‐tetrahydro‐5H‐1,3,4‐thiadiazolo[2,3‐b]quinazolin‐5‐one (3) were prepared. Derivatives of pyrimido[2,1‐b]benzothiazol‐2‐one (6) and of the isomeric 4‐one derivatives 8 were also synthesized. Structural identification was obtained by 1H‐nmr, ir and mass spectra.
Synthesis of pyrimidine derivatives by the reaction of ketene dithioacetals with amides
Authors: Kohra Shinya , Tominaga Yoshinori , Hosomi Akira 
Published: April 2009

AbstractReactions of methyl 2‐cyano‐3,3‐bis(methylthio)acrylate (1a) with carboxamides 2a‐g in the presence of sodium hydride in a mixture of benzene and N,N‐dimethylacetamide took place displacement with the methylthio group to give the corresponding methyl 3‐N‐acylamino‐2‐cyano‐3‐(methylthio)acrylates 3a‐g which were readily converted to the corresponding pyrimidine derivatives at reflux in methanol in good yields. Reactions of 2‐cyano‐3,3‐bis(methylthio)acrylonitrile (1b) with the carboxamides 2a‐f gave directly pyrimidine‐5‐carbonitrile derivatives 7a‐f. Ketene dithioacetals 1a,b smoothly reacted with thioamide 2g or urea 2h,i to give the expected pyrimidine derivatives 9,10a,b. Polyfunctionalized pyrimidines, thus obtained, were also used for the synthesis of fused pyrimidine derivatives.
Benzofurans. Ketene intermediates in the perkin reaction
Authors: Brady William T. , Gu Yi‐Qi 
Published: April 2009

AbstractThe intermediacy of ketenes in the intramolecular reaction of ketoacids with sodium acetate in acetic anhydride to form benzofurans is demonstrated. The Perkin reaction conditions are superior to the classical ketene generation method of triethylamine dehydrochlorination of the acid chloride.
Reactions of substituted phenacyl bromides with various bases: p‐methyl‐ and p‐methoxyphenacyl bromide. II
Authors: Baghdadchi Jamil , Chan Albert P. , Hutchinson James H. 
Published: April 2009

AbstractThe products obtained from the reaction of p‐methyl‐ and p‐methoxyphenacyl bromide with various bases are described.
The synthesis of 1,3‐dihydro‐1‐[1‐[(4‐methyl‐4H‐6H‐pyrrolo[1,2‐a][4,1]benzoxazepin‐4‐yl)methyl]‐4‐piperidinyl]‐2H‐benzimidazol‐2‐one (1:1) maleate (CGS 9343 B, potent calmodulin inhibitor)
Authors: Boyer S. , Blazier E. , Barabi M. , Long G. , Zaunius G. , Wasley J. W. F. , Hamdan A. 
Published: April 2009

AbstractA practical synthesis of the title compound7bis described in seven steps in approximately 10% overall yield. The key step in the synthesis is the formation of the unusual tricyclic ring system4viaacid catalyzed cyclization.
Polycondensed heterocycles. III. Synthesis of 5,11‐dioxo‐1,2,3,1 1a‐tetrahydro‐5H,11H‐ and 5‐oxo‐2,3,11,1 1a‐tetrahydro‐1H,5H‐pyrrolo[2,1‐c][1,4]benzothiazepine
Authors: Nacci V. , Garofalo A. , Anzini M. , Campiani G. 
Published: April 2009

AbstractThe syntheses of 5,11‐dioxo‐1,2,3,11a‐tetrahydro‐5H11H‐ and 5‐oxo‐2,3,11,11a‐tetrahydro‐1H,5H‐pyrrolo‐[2,1‐c][1,4]benzothiazepine 10 and 11 have been studied.The former was obtained by intramolecular cyclization with CDI of N‐(2‐mercaptobenzoyl)‐L‐proline 19, prepared on one hand by demethylation of N‐(2‐methylthiobenzoyl)‐L‐proline t‐butyl ester 15, obtained via the Pummerer rearrangement of the corresponding sulphoxide 17 and successive alkaline hydrolysis, and by deprotection of the mercapto ester 18 with TFA or trimethylsilyl iodide. The ester 15 was achieved by reaction of o‐(methylthio)benzoic acid 12 with L‐proline t‐butyl ester or by treatment of the corresponding acid chloride 13 with L‐proline and successive esterification of N‐(2‐methylthiobenzoyl)‐L‐proline 16. On the other hand the proline 19 was also obtained by reduction with sodium dithionite of (S)‐bis[2‐[[2‐(hydroxycarbonyl)‐1‐pyrrolidinyl]carbonyl]phenyl] disulphide 20, prepared by condensation of bis(2‐chlorocarbonylphenyl) disulphide 14 with L‐proline. The reduction of (S)‐bis[2‐[[2‐(chloromethyl)‐1‐pyrrolidinyl]carbonyl]phenyl] disulphide 28 with sodium borohydride in boiling ethanol afforded directly the benzothiazepinone 11 in 85% yield. The disulphide 28 was synthesized treating the corresponding alcohol 24 or N‐(2‐mercaptoben‐zoyl)‐L‐prolinol 25 with thionyl chloride. Compound 25 was obtained by demethylation of the corresponding methylthio ether 26 oxidized to sulphoxide 27 via the Pummerer rearrangement. The acid chloride 14 by condensation with (S)‐2‐(chloromethyl)pyrrolidine hydrochloride gave disulphide 28 as well. The acid chlorides 13 and 14 by reaction with L‐prolinol provided respectively alcohols 26 and 24.Attempts to cyclodehydrate the mercapto alcohol 25, obtained also by reduction of disulphide 24, failed.
New benzimidazole synthesis
Authors: Benincori T. , Sannicolò F. 
Published: April 2009

AbstractThermal or acid catalyzed cyclization of several N‐(N‐arylbenzimidoyl)‐1,4‐benzoquinoneimines 2 affords 1‐aryl‐6‐hydroxy‐2‐phenylbenzimidazoles 3 in fairly good yields. Structural proofs and kinetic support for the reaction mechanism are given.
A new highly efficient method for the synthesis of trans‐tetrahydro‐3,4‐furandiamine
Authors: Bitha Panayota , Lin Yang‐I 
Published: April 2009

AbstractA new four‐step, highly efficient synthesis of trans‐tetrahydro‐3,4‐furandiamine is described. Nitromercuration of 2,5‐dihydrofuran with sodium nitrite and mercuric chloride in aqueous solution followed by base catalyzed elimination yielded 3‐nitro‐2,5‐dihydrofuran which was aminated with ammonium hydroxide to give trans‐tetrahydro‐4‐nitro‐3‐furanamine. Catalytic reduction of this material afforded the desired product 5 in 37% overall yield.
A new synthesis of 2,3‐dihydrofuro[2,3‐b], [2,3‐c] and [3,2‐c]quinolines
Authors: Godard A. , Jacquelin J. M. , Queguiner G. 
Published: April 2009

AbstractA new synthesis of three isomeric dihydrofuroquinolines is described. This route via ortholithiation of O‐quinolyl carbamates is considerably more effective than that which proceeds via lithiation of alkoxyquinolines.
13C NMR studies of substituted 2,3‐diphenylindoles. Methyl and nitro derivatives
Authors: Erra‐Balsells R. 
Published: April 2009

AbstractThe 13C nmr spectra of a series of methyl‐ and/or nitro‐2,3‐diphenylindole derivatives are reported. The dependence of a) 1H and 13C methyl group shieldings on molecular geometry and b) the possibility that 13C nmr might be a useful tool in determining photochemical reactivity are discussed briefly.
New heterocyclic compounds derived from diethyl 2,5‐dioxo‐1,4‐cyclohexanedicarboxylate and 2‐aminobenzophenone
Authors: Kitahara Kiyoshi , Nishi Hisao 
Published: April 2009

AbstractThe synthesis and properties of a new class of heterocyclic compounds 5–8 derived from 2‐aminobenzo‐phenone and diethyl 2,5‐dioxo‐1,4‐cyclohexanedicarboxylate were investigated.
An asymmetric isoxazole annulation
Authors: Marron Brian E. , Schlicksupp Ludwig , Natale N. R. 
Published: April 2009

AbstractAn Asymmetric isoxazole annulation proceeds from the (S)‐O‐methoxyphenylalaninol imine of (RS)‐2‐phen‐ylpropionaldehyde (3). Deprotonation, quenching with 4‐chloromethyl‐3,5‐dimethylisoxazole, and hydrolysis produced isoxazolylaldehyde (5), whose structure was confirmed by single crystal X‐ray diffractometry. The absolute configuration of (‐)‐5 was established as (R)‐by chemical correlation to the known (S)‐(‐)‐4‐methyl‐4‐phenyl‐cyclohex‐2‐ene‐1‐one (7).
A new route to 1,2,4‐ triazoles and 1,3,4‐ thiadiazoles from 1‐acylbithiourea
Authors: Okawara Tadashi , Tateyama Yoshihiro , Yamasaki Tetsuo , Furukawa Mitsuru 
Published: April 2009

AbstractThe intramolecular cyclization of 1‐ acylbithiourea 1 gave 1,2,4‐triazole 2 and 1,3,4‐thiadiazole 3. The reaction of 1 with p‐toluenesulfonyl chloride in the presence of trithylamine afforded 3. Treatment of 1 with methyl iodide in the absence of any base yielded 2‐methylthio‐1,3,4‐thiadiazole 10 and 2‐imino‐ 1,3,4‐thiadiazoline 12.
Hydroxymethylation and aminomethylation of 6‐mercaptopurine and its derivatives
Authors: Siver Kevin G. , Sloan Kenneth B. , Waranis Robert P. , Saab Akram 
Published: April 2009

AbstractLabile aminomethyl and hydroxymethyl derivatives of 6‐mercaptopurine (I) (6‐MP) and S6‐acyloxymethyl‐6‐MP have been converted to stable acetyloxymethyl derivatives by their reaction with acetic anhydride. Analysis of the reaction products and comparison of their 'H nmr spectra and hplc chromatograms with those of acetyloxymethyl derivatives of known structures suggested 1) that the aminomethyl derivatives of 6‐MP were 7‐substituted derivatives, 2) that the aminomethyl derivative of S6‐acetyloxylmethyl‐6‐MP was a 9‐derivative, 3) that the hydroxymethyl derivative of 6‐MP was a mixture of 7‐substituted and S6,3‐disubstitu‐ted derivatives, and 4) that the hydroxymethyl derivative of S6‐pivaloyloxymethyl‐6‐MP was a 9‐substituted derivative. In addition, a previously unreported dialkyl derivative of 6‐MP VI was isolated from its reaction with aminomethylating agent and characterized. Analyses of the 'H nmr spectra and hplc chromatograms of the reaction of VI with acetic anhydride suggested that VI was a 1,7‐disubstituted derivative.
Acetal formation from formylthiophene‐2‐carboxylic acids and recalculation of σI and σR substituent constants of the acetal group by 13C NMR chemical shifts
Authors: Lamartina Liliana , Noto Renato , Arnone Caterina 
Published: April 2009

AbstractA uv‐visible, 1H and 13C nmr study has been carried out to show that 4‐, 1, and 5‐formylthiophene‐2‐carboxylic acids, 2, give acetals in methanol. The ms data have confirmed the acetal formation, which has been studied kinetically by the uv technique. The substituent chemical shifts induced on the carboxy carbon atom and on the endocyclic carbon atoms in the acetals formed from 1 and 2 and in the corresponding anions have been used to recalculate σI and σR values by means of a dual substituent parameter treatment of data.
The 2,1‐benzisothiazolo[2,3‐b]‐2,1‐benzisothiazole system, synthesis and properties
Authors: Mckinnon David M. , Duncan K. Ann 
Published: April 2009

Abstract2,2′‐Diaminodiphenylmethane and its 4,4′‐dibromo‐derivative both react with N‐sulfinylmethanesulfon‐amide to form 2,1‐benzisothiazole derivatives. Methylation or acetylation of these provides examples of the hypervalent sulfur 2,1‐benzisothiazolo[2,3‐b]‐2,1‐benzisothiazole system. The nmr spectra of these compounds are discussed.
1,3‐Dipolar cycloadditions of mesitonitrile oxide with (9‐fluorenylidene)‐aceto‐ and malono‐nitriles. Synthesis of mono‐ and bis‐1,2,4‐oxadiazolylmethane derivatives
Authors: Lianis Pygmalion S. , Rodios Nestor A. , Alexandrou Nicholas E. 
Published: April 2009

AbstractMesitonitrile oxide reacts with C ≡ N bond of (aryl)(9‐fluorenylidene)acetonitriles 1 forming in very good yields the corresponding 1,2,4‐oxadiazoles 2. Analogously also proceeds the reaction of mesitonitrile oxide with 9‐fluorenylidenemalonodinitrile (3) with the formation of bis‐1,2,4‐oxadiazole derivative 4.
Reactions of anthranilamide with isocyanates: A new facile synthesis of 2,3‐dihydro‐5H‐oxazolo[2,3‐b]quinazolin‐5‐one and 3,4‐dihydro‐2H,6H‐[1,3]oxazino[2,3‐b]quinazolin‐6‐one [1]
Authors: Chern Ji‐Wang , Shish Fang‐Jy , Chang Chau‐Dung , Chan Chao‐Han , Liu Kang‐Chien 
Published: April 2009

Abstract2,3‐Dihydro‐5H‐oxazolo[2,3‐b]quinazolin‐5‐one 5a was synthesized from anthranilamide 1 and 2‐chloro‐ethyl isocyanate either by a direct reflux in methanol, or by stirring at room temperature in acetonitrile leading to the intermediate, 2‐(2‐chloroethyl ureido)benzamide 6a which was subsequently cyclized on heating with an organic base. However, when compound 6a was refluxed with concentrated hydrochloric acid, it furnished 3‐(2‐chloroethyl)‐2,4‐dioxo‐1H,3H‐quinazoline 2a in good yields. 3,4‐Dihydro‐2H,6.H‐[1,3]‐oxazino[2,3‐b]quinazolin‐6‐one 5b, 3‐(3‐chloropropyl)‐2,4‐dioxo‐1H,3.H‐quinazoline 2b and 2‐(3‐chloropropyl ureido)benzamide 6b were obtained similarly from 1 and 3‐chloropropyl isocyanate.
The insertion and extrusion of heterosulfur bridges. XV. S‐bridging of 2,2′‐binaphthyl and 1‐(2‐naphthyl)cyclohexene. Studies on hydrodehalogenation during the reaction
Authors: Klemm L. H. , Stevens Michael P. , Iran Long K. , Sheley John 
Published: April 2009

AbstractRegioselectivity occurs in the sulfur‐bridging reactions of 2,2′‐binaphthyl (1) and 1‐(2‐naphthyl)cyclohexene (7) by means of hydrogen sulfide and a chromia‐alumina‐magnesia catalyst (designated I) in a flow apparatus at 550°. Thus, 1 gives a higher yield (6.1%) of dinaphtho[1,2–6:2′,l'‐d]thiophene from 1,1′‐bridging than of dinaphtho[1,2‐b:2′,3′‐d]thiophene (3.4%) from l,3′‐bridging. No product expected from 3,3′‐bridging was identified. Substrate 7 undergoes both dehydrogenation and bridging to yield 2‐phenylnaphthalene (8%), benzo[b]naphtho[2,1‐d]thiophene (9%) from alpha bridging, and benzo[b]naphtho[2,3‐d]thiophene (3%) from beta bridging into the naphthalene ring.Exploratory studies showed that either sulfided catalyst I or a sulfided molybdenum(VI) oxide‐alumina‐cobalt(II) oxide catalyst (II) effects hydrodehalogenation of various monohalo‐ and polyhaloarenes (where halo, X, is chloro or bromo) at 450–550°. In the biphenyl, phenanthrene, naphthalene, and pyrene systems, halogen was lost either under sulfur‐bridging conditions or under hydrogenolysis conditions, i.e. with methanol as a reactant. For every substrate the parent arene was isolated or identified as a reaction product. In selected experiments, acid HX was also identified in the effluent. Use of hydrogen sulfide as a reactant led to formation of dibenzothiophene and phenanthro[4,5‐bcd]thiophene as main products in the biphenyl and phenanthrene systems, respectively; while use of methanol as a reactant gave small amounts of methyl bromide (for X = Br) and methylarenes.
Synthesis and reactions of some 6‐(2‐hydroxy‐1‐naphthyl)‐1,2,4‐triazines
Authors: Eid Mohga M. , Kadry Azza M. , Hassan Ramadan A. 
Published: April 2009

Abstract4,5‐Benzocoumaran‐2,3‐dione condenses with semicarbazide and thiosemicarbazide at the 3‐position and the products obtained were converted to the corresponding 6‐(2‐hydroxy‐1‐naphthyl)‐1,2,4‐triazines. Reactions of these triazines with some reagents are described.
Selective method for the preparation of isomeric N‐alkyl and N‐aryl‐3(5)‐amino‐5(3)‐hydroxy‐1H‐pyrazole‐1‐carboxamides
Authors: Drummond James T. , Johnson Graham 
Published: April 2009

AbstractAs part of a program to develop novel mechanism based skeletal muscle relaxants we identified 5‐amino‐3‐hydroxy‐1H‐pyrazole‐1‐carboxamide (1) as a potential structural lead. This highly functionalized pyrazole was prepared via a published procedure [1] (Scheme 1, R1 = R1 = H), which utilized 3,5‐dimethyl‐1H‐pyrazole‐1‐carboxamide as an aminocarbonyl transfer reagent, to give with cyanoacethydrazide the semicarbazide intermediate 6. Base catalyzed cyclization of 6 afforded the initial lead compound. This reaction scheme was extended to the synthesis of additional 4‐alkyl‐ and 4‐aryl‐5‐amino‐3‐hydroxy‐1H‐pyrazole‐1‐carboxamides (Table 1).
Independent synthesis of 5‐hydroxytryptamine‐4,7‐dione ‐ the neurocytotoxic product of autoxidation of 5,7‐dihydroxytryptamine
Authors: Sinhababu Achintya K. , Borchardt Ronald T. 
Published: April 2009

AbstractSynthesis of 5‐hydroxytryptamine‐4,7‐dione hydrochloride (20) is described starting from 3‐bromo‐4,5‐dimethoxybenzaldehyde (6). Compound 6 was converted to 2,3,5‐tris(benzyloxy)benzaldehyde (10) in 4 steps. Nitromethylenation of 10 followed by nitration and subsequent reductive cyclization gave 4,5,7‐tris(benzyloxy)indole (13). Introduction of the aminoethyl (hydrochloride) side chain on C‐3 of 13, via the corresponding indole‐3‐acetonitrile, and subsequent debenzylation generated in situ, 4,5,7‐trihydroxytryptamine hydrochloride (19) which underwent rapid autoxidation in ethanol to give 20. 4,5,7‐Trihydroxyindole (21) and 3‐[2‐(ethoxycarbonylamino)ethyl]‐4,5,7‐trihydroxyindole (24), both generated in situ, were also found to undergo rapid autoxidation to the corresponding 5‐hydroxyindole‐4,7‐diones.
Synthesis and structure elucidation of N‐methyl‐4‐(2‐benzo‐γ‐pyronyl)‐1,2,3‐triazoles
Authors: Mouysset G. , Grassy G. , Payard M. , Commenges G. , Carpy A. , Couquelet J. 
Published: April 2009

AbstractWhen diazomethane was reacted with 2‐cyano chromones, three isomeric N‐methyltriazoles were obtained. They were isolated by liquid chromatography with three different solvents for elution. Complete elucidation of the structures was performed both by pmr and cmr spectrography; X‐ray analysis is in agreement with the proposed structures.
Cyclic homologs of xanthines.I. Imidazo[4,5‐e][1,4]diazepine‐5,8‐diones
Authors: Bridson Peter K. , Weirich Timothy P. 
Published: April 2009

AbstractA useful synthetic approach to variously alkylated 4,5,7,8‐tetrahydro‐6.H‐imidazo[4,5‐e][1,4]diazepine‐5,8‐diones is reported. These compounds are potentially interesting cyclic homologs of pharmacologically important alkylxanthines.
Synthesis of 2‐oxo‐3‐benzothiazolineacetyl chloride (7), 5‐chloro‐2‐oxo‐3‐benzothiazolineacetyl chloride (8) and derivatives
Authors: D'Amico John J. , Bollinger Frederick G. 
Published: April 2009

AbstractThe reaction of 2‐oxo‐3‐benzothiazolineacetic acid (5) and the 5‐chloro analogue 6 with thionyl chloride afforded the titled compounds 7 and 8. The reaction of 7 or 8 with substituted hydrazines, amines or substituted anilines, alcohols and mercaptans furnished the hydrazides 9–14, acetamides and acetanilides 16–21, esters 26–30 and thiolesters 31–37, respectively. Alternate routes for the synthesis of hydrazide 15, acetamides and acetanilides 22–25 and thiolesters 35–36 are described. The reaction of 2‐oxo‐3(2H)‐benzothi‐azolineacetonitrile with thioacetic acid under acidic conditions afforded 2‐oxo‐3‐benzothiazolineethanethio‐amide (38).
Synthesis of 1‐aryl‐5‐arylazo‐3‐phenylsulfonylpyrazol‐4‐ols from 1‐bromo‐3‐phenylsulfonyl‐2‐propanone
Authors: Takahashi Masahiko , Abe Hidetoshi , Tetsuka Takashi 
Published: April 2009

AbstractTreatment of 1‐bromo‐3‐phenylsulfonyl‐2‐propanone (1) with arenediazonium chloride gave 1‐aryl‐5‐arylazo‐3‐phenylsulfonylpyrazol‐4‐ols 5a‐h in 13–48% yields.