bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation of trimethylsilyl ethers of 3‐azetidinols. Scope and Limitations
Authors: Higgins Robert H. , Watson Monique R. , Faircloth William J. , Eaton Quentin L. , Jenkins Harvey 
Published: April 2009

AbstractPreparation of the trimethylsilyl ethers of 1‐alkyl‐3‐azetidinols from non‐hindered primary amines and epichlorohydrin by conversion of the intermediate 1‐(alkylamino)‐3‐chloro‐2‐propanols to their trimethylsilyl ethers by either N‐(trimethylsilyl)acetamide or by 1‐(trimethylsilyl)imidazole followed by ring closure in acetonitrile is described. This sequence of reactions fails for aromatic amines, but appears to be general for all primary aliphatic amines, although the condensation of hindered amines with epichlorohydrin occurs slowly. Several novel azetidinols, in which the N‐alkyl substituent itself contains a second heterocyclic system, are reported. In addition, the pKA's of several m. and p‐substituted 1‐benzylazetidinols correlates well with the Hammett equation.
The synthesis and transformations of 9H‐imidazo[1,2‐b]pyrazolo[4,3‐d]‐pyridazine and 9H‐pyrazolo[4,3‐d]‐s‐triazolo[4,3‐b]pyridazine derivatives
Authors: Stanovnik Branko , Furlan Borut , Kupper Marko , Malež Lidija , Štimac Anton , Tišler Miha , Žličar Marko 
Published: April 2009

AbstractThe nucleophilic and electrophilic substitutions of 6‐substituted 9,9‐dimethyl‐9H‐imidazo[1,2‐b]pyrazolo‐ [4,3‐d]pyridazines 2, nucleophilic substitutions of 6‐substituted 9,9‐dimethyl‐9H‐pyrazolo[4,3‐d]‐s‐triazolo‐ [4,3‐b]pyridazines 7 and some other transformations to give compounds 3 and 8, respectively, were studied. It was shown that both heterocyclic systems are stable under the conditions employed in these transformations.
Reaction of ketenes with N,N‐disubstituted α‐aminomethyleneketones. XIX. Synthesis of N,N‐disubstituted 4‐amino‐3‐phenyl‐2H‐furo[2,3‐h]‐1‐benzopyran‐2‐ones (4‐amino‐3‐phenylangelicins). Crystal and molecular structure of 3‐Phenylangelicin
Authors: Mosti Luisa , Schenone Pietro , Menozzi Giulia , Sancassan Fernando , Baccichetti Francarosa , Benetollo Franco , Bombieri Gabriella 
Published: April 2009

Abstract1,4‐Cycloaddition of phenylchloroketene to N,N‐disubstituted 5‐aminomethylene‐6,7‐dihydrobenzo[b]‐ furan‐4(5H)‐ones gave the corresponding adducts, namely N,N‐disubstituted 4‐amino‐3‐chloro‐3,4,5,6‐tetra‐ hydro‐3‐phenyl‐2H‐furo[2,3‐h]‐l‐benzopyran‐2‐ones II, which were dehydrochlorinated with DBN to N,N‐disubstituted 4‐amino‐5,6‐dihydro‐3‐phenyl‐2H‐furo[2,3‐h]‐1‐benzopyran‐2‐ones III. Compounds III afforded the title compounds IV by dehydrogenation with DDQ. In the cycloaddition step, 3‐phenylangelicin V, whose structure was confirmed by 1H‐nmr shift reagents data and by X‐ray crystal structure determination, was almost always formed, probably starting from II by dehydrochlorination, dehydrogenation and hydrogenolysis of the disubstituted amino group. Separation of V was achieved by alumina chromatography either in the cycloaddition step or, in most cases, in the dehydrochlorination step.3‐Phenylangelicin crystallizes in the trigonal system, space group R3, with cell parameters (hexagonal axes) a = b = 41.021(10), c = 3.888(2) Å. The angelicin moiety forms a dihedral angle of 42.1(1)° with the phenyl substituent. Disordered solvent molecules of ethyl acetate are clathrated in channels in the direction of the crystallographic axis c.
Amidrazones 11. Rearrangement of 1‐allyl‐substituted‐4,5‐dihydro‐1‐methyl‐1H‐pyrazolium bromides
Authors: Smith Richard F. , Dennis Lisa A. , Ryan William J. 
Published: April 2009

Abstract1‐Methyl‐2‐(2‐propenyl)‐3‐pyrazolidinimine (5) was obtained by treatment of 3‐amino‐4,5‐dihydro‐1‐methyl‐ 1‐(2‐propenyl)‐1H‐pyrazolium bromide (4) with ethanolic sodium ethoxide. Similar treatment of the analogous 2‐(2‐butenyl) and 2‐(3‐phenyl‐2‐propenyl)‐substituted salts 12 and 15 gave 1‐methyl‐2‐(1‐methyl‐2‐propenyl)‐3‐ pyrazolidinimine (13) and 1‐methyl‐2‐(1‐phenyl‐1‐propenyl)‐3‐pyrazolidinimine (16) respectively.
Synthesis, structural and conformational study of N‐β(or γ)‐acyloxyalkylnortropinones
Authors: Izquierdo M. L. , Gálvez E. , Burgos C. , Florencio F. 
Published: April 2009

AbstractA series of N‐β(γ)‐acyloxyalkylnortropinones have been synthesized and studied by 1H and 13C nmr spectroscopy, and the crystal structure of N‐[γ‐(p‐chlorophenylcarbonyloxy)propyl]nortropinone 4 has been determined by X‐ray diffraction. The compounds studied display in deuteriochloroform solution the same preferred conformation. The pyrrolidine and piperidone rings adopt a flattened N‐8 envelope and distorted chair conformation, puckered at N‐8 and flattened at C‐3 respectively, with the N‐substituent in axial position with respect to the piperidone ring. These results are in close agreement with that found for compound 4 in the crystalline state.
A facile synthesis of 2,4,8,10‐tetrahalo‐6,12‐diaryldibenzo[b,f][1,5]diazocines
Authors: Boruah R. C. , Sandhu J. S. 
Published: April 2009

Abstract3,5‐Dihalo‐2‐aminobenzophenones 2 on prolonged reflux in dry pyridine gave 2,4,8,10‐tetrahalo‐6,12‐ diaryldibenzo[b,f][1,5]diazocines 3 in high yields. Attempted condensation of 2 with glycine ester hydrochloride under identical reaction conditions failed to afford 1,4‐benzodiazepines.
Indole derivatives. 1. Synthesis of tetracyclic mesoionic pyrimido[3,2:2′,3′]‐as‐triazino[5′,6′‐b]indole‐2,4‐diones
Authors: Mbagwu Godwin O. , Bullock Boris , Greer Onza 
Published: April 2009

AbstractThe synthesis of the title compounds 5 has been accomplished by the thermal cyclocondensation of bis(2,4,6‐trichlorophenyl) malonates with the appropriately substituted alkyl er arylalkylaminotriazinoindole.
C‐Nucleosides. 8. Synthesis of 5‐hydroxy‐2‐(β‐D‐ribofuranosyl)pyridine
Authors: Maeba Isamu , Suzuki Makoto , Takahashi Naoko , Iijima Takashi , Furukawa Hiroshi 
Published: April 2009

AbstractThe synthesis of 5‐hydroxy‐2‐(β‐D‐ribofuranosyl)pyridine (12) from 2‐(2,3,5‐tri‐O‐benzoyl‐β‐D‐ribofuranosyl)furan (1) is described. Treatment of 1 with α‐methoxycarbamate in the presence of p‐toluenesulfonic acid in benzene at reflux temperature afforded furfurylcarbamate (2) and its α‐isomer in a 5/1 ratio. The anomerization was circumvented by treatment of 1 with α‐methoxycarbamate in the presence of boron trifluoride in benzene at room temperature. Compound 2 was electrochemically oxidized to give dihydrofuran 4. However, conversion of 4 into 11 was unsuccessful. Treatment of azide 8 with bromine and methanol afforded 9. Reduction of 9 with zinc powder gave dihydrofurfurylamine 10, in 80% yield. Treatment of this with concentrated hydrochloric acid in methanol yielded 11, which on deblocking with 5% sodium hydroxide aqueous solution gave 12.
Halogenated 3‐pyridylketones
Authors: Sutter Peter , Weis Claus D. 
Published: April 2009

AbstractThe oxidation of 2,6‐dichloro‐3‐benzylpyridines and bis(2,6‐dichloro‐3‐pyridyl)methanes, respectively, was accomplished using chromic trioxide in a highly acidic medium. The synthesis of several phenyl‐3‐(2,6‐dichloropyridyl)ketones and of bis(2,6‐dichloro‐3‐pyridyl)ketone are reported.
Synthesis of santonin related compounds
Authors: Tsuboi Sadao , Shinhama Koichi , Takeda Akira 
Published: April 2009

Abstract(±)‐1‐Nordesmotroposantonin (2), a thermolysis product of santonin, and its isomer, α‐(1,2,3,4‐tetrahydro‐1,7‐dihydroxy‐α,6‐dimethyl‐2‐naphthalene)acetic acid γ‐lactone (3) were synthesized from 4‐(4‐methoxy‐3‐ethylphenyl)butanoic acid.
Synthèse d'oxaphénalènes substitués en position 2 par un groupement électro‐attractif
Authors: Buisson Jean‐Pierre , Royer René 
Published: April 2009

AbstractIl est montré que la condensation de Rap [1] d'un composé halogéno‐méthylénique et d'un aldéhyde ortho‐ hydroxylé peut ětre effectuée en péri, avec les aldéhydes hydroxy‐8 naphtoïques‐1.
Reinvestigation of the condensation of 2‐hydrazinobenzothiazole with ethyl acetoacetate
Authors: Peet Norton P. , Sunder Shyam , Barbuch Robert J. , Whalon Michael R. , Huffman John C. 
Published: April 2009

AbstractThe reaction of 2‐hydrazinobenzothiazole (1) with ethyl acetoacetate has twice been reported to yield a fused triazepinobenzothiazolone, namely, 3‐methyl[1,2,4]triazepino[3,4‐b]benzothiazol‐5(4H)‐one (4). We have repeated this work and reassigned the reaction product as 2‐(2‐benzothiazolyl)‐1,2‐dihydro‐5‐methyl‐3H‐pyrazol‐3‐one (5) on the basis of X‐ray crystallography.
Some novel mesoionic bispurinone analogs: Studies on preparation and characterization
Authors: Mbagwu Godwin O. , Garland Rickie 
Published: April 2009

AbstractThe preparation of the first examples of class II mesoionic bispurinones is described. Arylaminobithiazole 3 is cyclized by condensation with bis(2,4,6‐trichlorophenyl) methylmalonate to yield anhydro 3,3′‐bis(6‐methyl‐8‐aryl‐5‐hydroxy‐7‐oxothiazolo[3,2‐a]pyrimidinium hydroxide).
Conjugated systems derived from piperazine‐2,5‐dione
Authors: Katritzky Alan R. , Fan Wei‐Qiang , Szajda Maria , Li Qiao‐Ling , Caster Kenneth C. 
Published: April 2009

AbstractThe preparation of mono‐ and of symmetrical and unsymmetrical bis‐ylidine derivatives of piperazine‐ 2,5‐dione is described. The uv‐visible absorption of the products is correlated with acceptor/donor character of the substituents.
On the mechanism of a novel 3(2H)‐Furanone‐2(5H)‐furanone rearrangement
Authors: Mack Robert A. , Carroll Patrick J. , Georgiev Vassil St. 
Published: April 2009

AbstractThe isolation of a stable intermediate product and the mechanism of a novel 3(2H)‐furanone‐2(5H)‐furanone rearrangement that led to the facile preparation of a new class of γ‐lactone amides 2 and 4 are discussed.
A new regioselective synthesis of 2,3,4,5‐tetrahydro‐6H‐oxepino[3,2‐c]pyran‐6‐ones, and [1]benzopyran‐6‐ones
Authors: Bravo Pierfrancesco , Frigerio Massimo , Ticozzi Calimero 
Published: April 2009

AbstractThrough an anti‐Markovnikow hydration of some olefin derivatives of 4‐hydroxy‐2‐pyrones, and 4‐hydroxy‐coumarins, followed by a regioselective intramolecular dehydration, involving the primary alcohols obtained and the enolic oxygen of the rings, promoted by Amberlyst 15 in boiling toluene, the new heterocycles 2,3,4,5‐tetrahydro‐6H‐oxepino[3,2‐c]pyran‐6‐one (3) and [1]benzopyran‐6‐ones ba,c were obtained in fair yields.
Etude des voies d'accès aux aminométhyl benzo[g]isoquinoléinediones‐5,10. Mise en évidence d'une substitution anormale au cours de la réaction de Bischler‐Napieralski en série diméthoxy‐1,4 naphthalène
Authors: Croisy‐Delcey Martine , Huel Christiane , Bisagni Emile 
Published: April 2009

AbstractDans les conditions de la réaction de Bischler‐Napieralski, la cyclisation des acétamides dérivés des (diméthoxy‐1,4 et triméthoxy‐1,4,8 naphtyl)‐2 éthyl acétamides s'effectue principalement en position angulaire, par substitution du groupement méthoxy‐1. Les aminométhyl‐1 azaanthraquinones‐9,10 sont néanmoins accessibles à partir des aminométhyl‐1 isoquinoléinediones‐5,8, par condensation avec le diacétoxy‐1,4 butadiène‐1,3.
Potential cerebral perfusion agents. Synthesis and evaluation of a 1,4‐disubstituted dihydropyridine analogue
Authors: Srivastava Prem C. , Knapp Furn F. , Pruitt Carol D. 
Published: April 2009

AbstractThe synthesis of a 1,4‐disubstituted dihydropyridine, 1‐(E‐1[125I]iodo‐1‐penten‐5‐yl)‐4‐(β‐N‐acetylaminoethyl)‐1,4‐dihydropyridine ([125I]10), is described. Acetylation of 4‐(β‐aminoethylpyridine) with acetic anhydride followed by condensation with E‐1‐borono‐5‐iodo‐1‐pentene (7) gave 1‐(E‐1‐borono‐1‐penten‐5‐yl)‐4‐(β‐N‐acetylaminoethyl)pyridinium iodide (8). Chloramine‐T and sodium iodide iodination of 8 gave the corresponding E‐1‐iodo compound 9 which was reduced with sodium borohydride to furnish 1‐(E‐1‐iodo‐1‐penten‐5‐yl)‐4‐(β‐N‐acetylaminoethyl)‐1,4‐dihydropyridine (10). The corresponding radioiodinated compound was prepared similarly using Na[125I]. The tissue distribution studies in rats indicate that [125I]10 crosses the blood brain barrier (0.49% dose/g in the brain) but gradually washes out from the brain.
Long range heteronuclear chemical shift correlation with one bond modulation decoupling: Phenanthro[1,2‐b]thiophene
Authors: Kruger Diana K. , Martin Gary E. , McKenney J. Dew , Castle Raymond N. 
Published: April 2009

AbstractLong range heteronuclear chemical shift correlation has become an extremely useful technique for complex spectral assignment and structure elucidation. The sensitivity is higher than that afforded by 13C‐13C double quantum INADEQUATE experiment. The long range heteronuclear correlation provides the means of establishing connectivities across heteroatoms. Early attempts to use long range heteronuclear chemical shift correlation by simply optimizing the delays for long range couplings met with varied success. Long range coupling responses to protonated carbon resonances can be modulated by the one bond coupling of the protonated carbon. These modulations can lead to precipitous valleys in the response curve and a corresponding loss of connectivity information. A newly reported pulse sequence employing a BIRD pulse midway through the Δ2 refocusing delay “decouples” one bond modulation effects substantially increasing the likelihood of observing the desired connectivities. The application of this technique is reported for phenanthro[1,2‐b]thiophene. Unequivocal assignment of the title compound is reported using heteronuclear chemical shift correlation and long range correlation with modulation decoupling. The assignment took a total of < 15 hours of spectrometer time.
Preparations of 2‐azabicyclo[2.2.2]octa‐5,7‐dien‐3‐ones and 7‐azabicyclo[4.2.0]octa‐2,4‐dien‐8‐ones from addition reactions of 2‐pyridones
Authors: Somekawa Kenichi , Okumura Yasuo , Uchida Kunitomi , Shimo Tetsuro 
Published: April 2009

AbstractThe low temperature photoaddition of 2‐pyridone with dimethyl acetylenedicarboxylate gave a [4 + 2]‐cycloadduct and a [2 + 2]‐cycloadduct across the 5,6‐position of 2‐pyridone. Their formations were competing with a Michael reaction of the two substrates at the room temperature reaction. The reactions of other pyridones with dimethyl acetylenedicarboxylate gave [2 + 2]‐ and/or [4 + 2]‐cycloadducts. The [2 + 2]‐cycloadducts underwent an intriguing rearrangement to fused β‐lactams.
Synthèse et stéréochimie de perhydrocyclopenta[b]furannones‐3‐cis et perhydrocyclopenta[b]furannols‐3‐cis
Authors: Dolmazon René 
Published: April 2009

AbstractUne voie d'accès à de nouveaux perhydrocyclopenta[b]furannols‐3‐cis et perhydrocyclopenta[b]furannones‐3‐cis est décrite. Leurs configurations et conformations sont établies par spectroscopie rmn 1H et 13C. Une certaine rigidité est observée au niveau de la jonction des deux cycles. Le cycle tétrahydrofurannone‐3 adopte une conformation mobile entre les formes C, et C2, dépendante du substituant en position 2.
A new improved synthesis and X‐ray crystal structure of [1,4]dithiino[2,3‐b]‐1,4‐dithiin
Authors: Varma K. S. , Sasaki N. , Clark R. A. , Underhill A. E. , Simonsen O. , Becher J. , Bøwadt S. 
Published: April 2009

Abstract[1,4]Dithiino[2,3‐b]‐1,4‐Dithiin (3) has been synthesised in high yield by a one‐step procedure starting with sodium 1,3‐dithiole‐2‐thione‐4,5‐dithiolate (2). The X‐ray crystal structure shows non‐planarity of the fused ring system as well as short intermolecular S ⃜S contacts.
Synthesis of 5,6‐dihydro‐4H‐thiopyran‐4‐ones
Authors: Becher Jan , Brøsndum Klaus , Hansen Poul , Jacobsen Jens Peter Jan 
Published: April 2009

AbstractThe anions of 1,4‐diaryl‐3‐buten‐2‐ones 1 reacts with arylisothiocyanates, yielding intermediates 4 which can ring close to 5,6‐dihydro‐4H‐thiopyran‐4‐ones 5. Under similar reaction conditions ethyl 3‐oxo‐4‐pentenoates 7 gives the 6‐spiropyrans 9. Methylation of 3 gives the S‐methylated open form 6.
Synthesis of dimethoxy‐ and dioxano‐annellated benzofuroxans from o‐dinitroarenes
Authors: Eswaran S. V. , Sajadian S. K. 
Published: April 2009

AbstractThermolysis of 4,5‐dinitroveratrole 1a in the presence of sodium azide and dimethylsulfoxide gives the new 5,6‐dimethoxybenzofuroxan, 2a, whereas 3,4,5‐trinitroveratrole led to the new 5(7),6‐dimethoxy‐4‐nitrobenzofuroxans 2e, 3e via a nucleophilic substitution of a nitro group by azide ion and pyrolytic ring closure. This method provides a simpler route to the known 1,3‐benzodioxano[5,6‐c]furoxan, 2b and 1,4‐benzodioxano[6,7‐c]furoxan 2c, as well.
Ambident anion chemistry: The reaction of sterically‐hindered phenolate anions with 1H‐pyrrole‐2,5‐diones
Authors: Pastor Stephen D. , Hessell Edward T. 
Published: April 2009

AbstractThe reaction of N‐phenylmaleimide, 4a, with sodium 2,6‐di‐t‐butylphenolate, 5a, in dimethylsulfoxide (DMSO) resulted a complex oligomeric mixture. The dimer 8 was isolated from the reaction of the N‐alkyl‐maleimide 4b with 5a in DMSO. The reaction of 4a with 5a in tetrahydrofuran (THF), which is an aprotic solvent that is known to promote ion pairing, resulted in the isolation of a low yield of 6a. The reaction of 4a with 5a in the hydrogen‐bonding solvent t‐butyl alcohol gave 6a in slightly higher yield. The N‐alkylpyrrolidine‐2,5‐diones 6c‐f were obtained by the reaction of the maleimides 4c‐e with the corresponding sodium phenolate 5a‐b in t‐butyl alcohol reaction medium. The isolated yield of product increased with the size of the N‐alkyl substituent of the maleimide. Surprisingly, the reaction of the 2,6‐dimethylphenolate 5c with 4d led to the isolation of the dimer 10 with the formation of a quaternary carbon atom. The yield of 6a was observed to counterion dependent, increasing in the order Na+ < Li+ < MgBr+ in t‐butyl alcohol. The bismaleimides 12 and 14 were obtained by the reaction of either 11 or 13 with 5d in THF.
Reactions of furoxano[3,4‐b]quinoxaline with alkynes and alkenes. Synthesis of pyrazino[2,3‐b]quinoxaline 1,4‐dioxides
Authors: Vrettou Maria S. , Gallos John K. , Nicolaides Demetrios N. 
Published: April 2009

AbstractPyrazino[2,3‐b]quinoxaline 1,4‐dioxides 3a‐e were prepared by reacting Furoxano[3,4‐b]quinoxaline with alkynes and alkenes.
Some novel reactions of 2‐amino‐4‐methyloxazole with aldehydes: Aryl and alkyl hydoxymethylation at C‐5
Authors: Khan Humaid R. , Crank G. , Jesdapaulpaan S. 
Published: April 2009

Abstract2‐Amino‐4‐methyloxazole reacts with aldehydes to give products having a hydroxymethyl function at C–5. No Schiff's bases were formed. Reactions seem to be confined to 4‐alkyl substituted‐2‐aminooxazoles as 2‐aminooxazole and its 4‐phenyl and 2‐acetomido derivatives fail to react with aldehydes. The nature of the aldehyde affects the amount of the product formed.
Synthesis of 4‐vinylquinoline: Pyrolytic rearrangement of the 4‐(1‐hydroxyethyl)quinoline and related derivatives
Authors: Rodriguez J. G. , Benito Y. 
Published: April 2009

AbstractThe synthesis of 4‐vinylquinoline has been carried out by means of the Wittig reaction between 4‐quino‐linecarbaldehyde and the methyl triphenylphosphonium ylide in dimethyl sulphoxide in good yield. Dehydration of the 4‐(1‐hydroxyethyl)quinoline and their xanthate derivative, give equimolar amounts of 4‐ethylquinoline and 4‐acetylquinoline while small amounts of 4‐vinylquinoline were found. Dehydrochlorination of 4‐(1‐chloroethyl)quinoline in ethanol‐sodium hydroxide provides 4‐ethyl‐3‐ethoxyquinoline in good yield, but 4‐vinylquinoline is a minor reaction product.
Novel synthesis of (−)‐trans‐Δ9,11‐tetrahydrocannabinol
Authors: Banijamali Ali R. , Makriyannis Alexandros 
Published: April 2009

AbstractAddition of hydrogen chloride gas to a solution of Δ8‐tetrahydrocannabinol in dry dichloromethane at ‐60° in the presence of zinc chloride results in the formation of a higher concentration of 9‐α‐chlorohexa‐hydrocannabinol (75%) than the thermodynamically more stable 9‐β‐chlorohexahydrocannabinol (25%). The two isomers can be separated by reverse‐phase hplc. Elimination of hydrogen chloride from 9‐α‐chlorohexa‐hydrocannabinol using potassiumt‐amylate under anhydrous conditions gives exclusively Δ9,11‐tetrahydrocannabinol in overall yield of 65%.
A new and improved synthesis of 6‐aryl‐1,2,4‐triazolo[4,3‐b]pyridazines
Authors: Lieberman Daniel F. , Albright J. Donald 
Published: April 2009

AbstractA new and improved synthesis of 6‐aryl‐1,2,4‐triazolo[4,3‐b]pyridazines is described. This methodology provides the title compounds under mild conditions and in high yields. The first step comprises the condensation of an aryl methyl ketone with a 4‐amino‐1,2,4‐triazole in toluene heated at reflux. The second step involves the condensation of that imine and t‐butoxybis(dimethylamino)methane in tetrahydrofuran at ambient temperature. The third step constitutes the pyridazine ring closure to the title compounds in acetic acid heated at reflux.
The oxidative‐rearrangement of nitrogen heterocycles with lead tetraacetate and t‐butyl hypochlorite
Authors: Zey Robert L. 
Published: April 2009

AbstractMechanisms for the lead tetraacetate and t‐butyl hypochlorite oxidation of 1,4‐dihydro‐3(2H)‐cinnolinones and 1‐amino‐2‐indolinones are discussed. Evidence for the lack of a nitrene intermediate is given.
Reaction of 5H‐dibenz[b,f]azepine with t‐butyl hypochlorite: An aromatic nitrenium ion intermediate?
Authors: Cann Michael C. , Lezinsky David 
Published: April 2009

AbstractThe reaction of 5H‐dibenz[b,f]azepine with t‐butyl hypochlorite and this same reaction in the presence of silver(I) were studied in an attempt to generate dibenz[b,f]azatropylium, an aromatic nitrenium ion. Analysis of the product mixture from this reaction mitigate against formation of this ion. An alternate mechanism is presented.
Pyridazines. XXXVII. Novel triazanaphthalene derivatives via intramolecular cyclization reactions of vic‐disubstituted pyridazines
Authors: Boamah Philip Yaw , Haider Norbert , Heinisch Gottfried , Moshuber Jöran 
Published: April 2009

Abstract8‐Phenylpyrido[3,4‐d]pyridazines bearing various amino substituents at C‐5 (7a‐d, 8) were prepared from ethyl 5‐benzyl‐4‐pyridazinecarboxylate 1 via the fused pyridone 5. The isomeric 4‐phenylpyrido[2,3‐d]pyridazines having the amino functions attached to C‐2 (10a‐f) were obtained by a one‐pot cyclization of the amino ketone 1 with appropriate acetamide acetals. These novel triazanaphthalene derivatives are of interest as analogues of diuretic and antithrombotic agents.
The synthesis of XTT: A new tetrazolium reagent that is bioreducible to a water‐soluble formazan
Authors: Paull Kenneth D. , Shoemaker Robert H. , Boyd Michael R. , Parsons Jack L. , Risbood Prabhakar A. , Barbera William A. , Sharma Mahenda N. , Baker David C. , Hand Elli , Scudiero Dominic A. , Monks Anne , Alley Michael C. , Grote Manfred 
Published: April 2009

AbstractA new tetrazolium salt, XTT, has been synthesized. XTT is reduced by a considerable variety of cell lines to a water‐soluble formazan. XTT appears to merit further investigation as a reagent for broader application to cell culture assay systems.
Preparation of hydrogenated azepino[3,2,1‐hi]indoles
Authors: Katayama Hajime , Maeda Kaijiro , Kaneko Kimiyoshi 
Published: April 2009

AbstractA general method for the preparation of 4,5‐dihydro‐, 1,2,4,5‐tetrahydro‐, 4,5,6,7‐tetrahydro‐ and 1,2,4,5,6,7‐hexahydroazepino[3,2,1‐hi]indoles was established by using intramolecular Friedel‐Crafts alkylation of chloromethylthioacetamide as a crucial step.
On the reaction of α‐(2‐hydroxyphenoxy)alkylketones with dimethylsulphoxonium methylide. A novel route to 2‐substituted‐2,3‐dihydro‐2‐hydroxymethyl‐1,4‐benzodioxins
Authors: Salimbeni Aldo , Manghisi Elso , Arnone Alberto 
Published: April 2009

AbstractA new route to 2‐substituted‐2,3‐dihydro‐2‐hydroxymethyl‐1,4‐benzodioxins 3 based on the reaction of α‐(2‐hydroxyphenoxy)alkylketones 1 with dimethylsulphoxonium methylide in dimethylsulphoxide is reported. Besides the desired compounds 3, the isomeric 2H‐3,4‐dihydro‐1,5‐benzodioxepines 4 were also isolated, generally as minor products. The concurrent formation of 3 and 4 has been interpreted as occurring through the intermediate oxiranes 2, which can undergo intramolecular nucleophilic attack at either of the carbon atoms of the epoxy ring.