- Stereochemical issues related to the synthesis of 7,10-dimethyl- 7,10,16,16a-tetrahydro-11H-quinazolino[2',3':3,4]pyrazino-[1,2-b]β- carboline-5,8-diones
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Condensation reactions between anthranilic acid and iminoethers derived from 2,3,6,7,12,12a-hexahydropyrazino[1,2-b]β-carboline-1,4-diones 3-8 to give the title hexacyclic compounds were studied from a stereochemical point of view. The configuration was r
- Madrigal, Antonio,Grande, Mercedes,Avendano, Carmen
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Read Online
- Ruthenium(ii)-catalyzed synthesis of indazolone-fused cinnolines via C-H coupling with diazo compounds
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A robust, efficient and scalable method for the synthesis of 12H-indazolo[2,1-a]cinnolin-12-ones was developed. Significantly, a less developed cationic complex [Ru(p-cymene)(MeCN)3(SbF6)2] was found to be effective for th
- Su, Lin,Yu, Zheng,Ren, Peiling,Luo, Zhi,Hou, Wei,Xu, Hongtao
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Read Online
- 'Second-generation' 1,2,3-triazole-based inhibitors of: Porphyromonas gingivalis adherence to oral streptococci and biofilm formation
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Several 'second-generation' click inhibitors of the multi-species biofilm propagated by the adherence of the oral pathogen Porphyromonas gingivalis to Streptococcus gordonii were synthesized and evaluated. The design of the structures was based on the results obtained with the first-generation diphenyloxazole 'click' inhibitors which bear suitable hydrophobic and polar groups within a dual scaffold molecule bearing a 1,2,3-triazole spacer. The structures of the synthetic targets reported herein now consist of a triazolyl(phenylsulfonylmethyl) and a triazolyl(phenylsulfinylmethyl) spacer which joins a 4,5-diphenyloxazole with both phenyl rings bearing lipophilic substituents. The triazolyl "linker" group is formed by a click reaction between the 4-azido(phenylsulfonyl/sulfinylmethyl) oxazoles and acetylenic components having aryl groups bearing hydrophobic substituents. The 1,3,5-trisubstituted-2,4,6-triazine scaffold of the most active click compounds were modeled after the structural motif termed the VXXLL nuclear receptor (NR) box. When substituted at the 3- and 5-positions with 2- and 4-fluorophenylamino and N,N-diethylamino units, the candidates bearing the 1,3,5-trisubstituted-2,4,6-triazine scaffold formed a substantial subset of the second-generation click candidates. Four of the click products, compounds 95, 111, 115 and 122 showed inhibition of the adherence of P. gingivalis to S. gordonii with an IC50 range of 2.3-4.3 μM and only 111 exhibited cytotoxic activity against telomerase immortalized gingival keratinocytes at 60 μM. These results suggest that compounds 95, 115, 122, and possibly 111 represent the most suitable compounds to evaluate for activity in vivo.
- Patil, Pravin C.,Tan, Jinlian,Demuth, Donald R.,Luzzio, Frederick A.
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p. 268 - 279
(2019/03/02)
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- Synthesis of Diverse Nitrogen Heterocycles via Palladium-Catalyzed Tandem Azide–Isocyanide Cross-Coupling/Cyclization: Mechanistic Insight using Experimental and Theoretical Studies
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A rapid and elegant tandem azide–isocyanide cross-coupling/cyclization protocol has been developed based on a nitrene transfer reaction. The palladium-catalyzed ligand-free methodology led to the synthesis of three different heterocyclic scaffolds with excellent atom/step/redox economy. Studies based on first-principles-based quantum calculations and control experiments unraveled a concerted process of nitrene transfer reaction on isocyanides, ruling out the metallaaziridine intermediate reported earlier. This finding could pave the way for novel applications of nitrene transfer reactions to generate bioactive heterocycles. (Figure presented.).
- Ansari, Arshad J.,Pathare, Ramdas S.,Maurya, Antim K.,Agnihotri, Vijai K.,Khan, Shahnawaz,Roy, Tapta Kanchan,Sawant, Devesh M.,Pardasani, Ram T.
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p. 290 - 297
(2017/12/07)
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- Insights into the Desaturation of Cyclopeptin and its C3 Epimer Catalyzed by a non-Heme Iron Enzyme: Structural Characterization and Mechanism Elucidation
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AsqJ, an iron(II)- and 2-oxoglutarate-dependent enzyme found in viridicatin-type alkaloid biosynthetic pathways, catalyzes sequential desaturation and epoxidation to produce cyclopenins. Crystal structures of AsqJ bound to cyclopeptin and its C3 epimer ar
- Liao, Hsuan-Jen,Li, Jikun,Huang, Jhih-Liang,Davidson, Madison,Kurnikov, Igor,Lin, Te-Sheng,Lee, Justin L.,Kurnikova, Maria,Guo, Yisong,Chan, Nei-Li,Chang, Wei-Chen
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supporting information
p. 1831 - 1835
(2018/01/27)
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- Oxazoles for click chemistry II: Synthesis of extended heterocyclic scaffolds
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Abstract New routes to 2,4,5-trisubstituted oxazoles were established whereby the substitution pattern was established by the structure of the starting nonsymmetrical acyloins. 2-Chloromethyl-4, 5-disubstituted oxazoles were prepared by refinements of an earlier described process whereby chloroacetyl esters of symmetrical and nonsymmetrical acyloins were cyclized using an ammonium acetate/acetic acid protocol. After substitution is effected, the azide moiety is then installed by substitution under mild conditions. While dibrominated and iodinated phenyloxazoles are required for further synthetic elaboration, the cyclization reaction was found to be very sensitive to the relative positions of the halogens in the starting materials.
- Patil, Pravin C.,Luzzio, Frederick A.,Demuth, Donald R.
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supporting information
p. 3039 - 3041
(2015/05/27)
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- Intramolecular azide to alkene cycloadditions for the construction of pyrrolobenzodiazepines and azetidino-benzodiazepines
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The coupling of proline- and azetidinone-substituted alkenes to 2-azidobenzoic and 2-azidobenzenesulfonic acid gives precursors that undergo intramolecular azide to alkene 1,3-dipolar cycloadditions to give imine-, triazoline- or aziridine-containing pyrr
- Hemming, Karl,Chambers, Christopher S.,Jamshaid, Faisal,O'Gorman, Paul A.
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p. 16737 - 16756
(2015/01/09)
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- Azide based routes to tetrazolo and oxadiazolo derivatives of pyrrolobenzodiazepines and pyrrolobenzothiadiazepines
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Tetrazolo- and 1,2,4-oxadiazolo-fused derivatives of the antitumour, antibiotic, DNA-interactive pyrrolo[2,1-c][1,4]benzodiazepines and their pyrrolobenzothiadiazepine derivatives have been produced as analogues of a 1,2,3-triazolo-fused pyrrolobenzothiad
- Hemming, Karl,Chambers, Christopher S.,Hamasharif, Muslih S.,Jo?o, Heidi,Khan, Musharraf N.,Patel, Nilesh,Airley, Rachel,Day, Sharn
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p. 7306 - 7317
(2016/02/03)
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- An efficient one-pot strategy for the synthesis of triazole-fused 1,4-benzodiazepinones from n-substituted 2-azidobenzamides
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A catalyst-free, one-pot strategy for the synthesis of 1,2,3-triazole-fused 1,4-benzodiazepinone derivatives from N-substituted 2-azidobenzamides and propargyl bromide, in the presence of a base, is reported. The products are formed in good to excellent y
- Majumdar,Ganai, Sintu
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p. 2619 - 2625
(2013/09/24)
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- Catalytic Staudinger/aza-Wittig sequence by in situ phosphane oxide reduction
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A Staudinger/aza-Wittig reaction sequence is described that is catalytic in phosphorus. Towards this end, the phosphane oxide is reduced in situ by diphenylsilane, which allows for substoichiometric amounts of the catalyst 5-phenyldibenzophosphole to be used. The substrate scope is investigated and benzoxazoles, benzodiazepine imidates and a 2-methoxypyrrole were successfully synthesized. These investigations show that a fast aza-Wittig reaction is required to obtain high yields. A catalytic Staudinger/aza-Wittig reaction sequence, involving in situ phosphane oxide reduction, was successfully developed. Benzoxazoles, benzodiazepine imidates and 2-methoxypyrrole were synthesized without phosphane oxide waste products. Copyright
- Van Kalkeren, Henri A.,Te Grotenhuis, Colet,Haasjes, Frank S.,Hommersom,Rutjes, Floris P. J. T.,Van Delft, Floris L.
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p. 7059 - 7066
(2013/11/06)
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- Multicomponent assembly processes for the synthesis of diverse yohimbine and corynanthe alkaloid analogues
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A strategy involving a Mannich-type multicomponent assembly process followed by a 1,3-dipolar cycloaddition has been developed for the rapid and efficient construction of parent heterocyclic scaffolds bearing indole and isoxazolidine rings. These key intermediates were then readily elaborated using well-established protocols for refunctionalization and cross-coupling to access a diverse 180-member library of novel pentacyclic and tetracyclic compounds related to the Yohimbine and Corynanthe alkaloids. Several other new multicomponent assembly processes were developed to access dihydro-β- carboline-fused benzodiazepines, pyrimidinediones, and rutaecarpine derivatives.
- Granger, Brett A.,Wang, Zhiqian,Kaneda, Kyosuke,Fang, Zhenglai,Martin, Stephen F.
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supporting information
p. 379 - 386
(2013/07/26)
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- Triplex-forming ability of oligonucleotides containing 1-aryl-1,2,3- triazole nucleobases linked via a two atom-length spacer
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Phosphoramidites containing 2-propynyloxy or 1-butyn-4-yl as nucleobase precursors were synthesized and introduced into oligonucleotides using an automated DNA synthesizer. Copper-catalyzed alkyne-azide 1,3-dipolar cycloaddition of the oligonucleotides wi
- Hari, Yoshiyuki,Nakahara, Motoi,Obika, Satoshi
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p. 5583 - 5588
(2013/09/02)
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- Total synthesis of rutaecarpine and analogues by tandem azido reductive cyclization assisted by microwave irradiation
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The total synthesis of rutaecarpine and several analogues has been developed by using an azido reductive cyclization process starting from substituted azido benzoic acids. The intramolecular azido reductive cyclization step was performed with triphenylphosphine or Ni2B in HCl-MeOH (1 M) using microwave irradiation. This synthetic route is amenable for the generation of a library of quinazolinone compounds. Georg Thieme Verlag Stuttgart - New York.
- Kamal, Ahmed,Reddy, M. Kashi,Reddy, T. Srinivasa,Santos, Leonardo Silva,Shankaraiah, Nagula
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scheme or table
p. 61 - 64
(2011/02/25)
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- Synthesis and diversification of 1,2,3-triazole-fused 1,4-benzodiazepine scaffolds
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A substituted heterocyclic scaffold comprising a 1,4-benzodiazepine fused with a 1,2,3-triazole ring has been synthesized and diversified via a variety of refunctionalizations. The strategy features the rapid assembly of the scaffold by combining 3-4 reac
- Donald, James R.,Martin, Stephen F.
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supporting information; experimental part
p. 852 - 855
(2011/04/26)
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- Multicomponent assembly strategies for the synthesis of diverse tetrahydroisoquinoline scaffolds
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Several novel multicomponent assembly processes have been developed for the rapid and efficient assembly of various heterocyclic scaffolds bearing a tetrahydroisoquinoline core, each of which allows for facile derivatization to access a diverse array of compounds. This work led to the serendipitous discovery of a new method for the synthesis of a fused quinazolone ring system, which was applied to a one-step total synthesis of the quinazolinocarboline alkaloid rutaecarpine.
- Granger, Brett A.,Kaneda, Kyosuke,Martin, Stephen F.
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supporting information; experimental part
p. 4542 - 4545
(2011/10/09)
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- First total synthesis of (-)-Circumdatin H, a novel mitochondrial NADH Oxidase inhibitor
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An efficient and highly convergent synthesis of the mitochondrial NADH oxidase inhibitor (-)-circumdatin H is described. The strategy employs the intramolecular Eguchi aza-Wittig protocol as a key step to install the crucial central core BC ring system, leading to the first total synthesis of the target molecule. Georg Thieme Verlag Stuttgart · New York.
- Bose, D. Subhas,Chary, M. Venu
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experimental part
p. 643 - 650
(2010/04/30)
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- Intramolecular azide-alkyne [3+2] cycloaddition: A versatile route for the synthesis of 1,2,3-triazole fused dibenzo[1,5]diazocine derivatives
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A facile synthesis of [1,2,3]triazolo dibenzo[1,5]diazocines by intramolecular Huisgen 1,3-dipolar cycloaddition of azide with alkynes has been achieved. The methodology offers clean reaction and easy isolation of products in excellent yields. Georg Thiem
- Majumdar,Ray, Krishanu,Ganai, Sintu
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body text
p. 2101 - 2105
(2010/08/20)
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- Synthesis of nitrogen heterocycle-fused 1,2,4-benzothiadiazine-1,1-dioxide, quinazolinone, and pyrrolidinone derivatives with a guanidine joint via sequential aza-Wittig reaction/intramolecular NH-addition cyclization/nucleophilic substitution ring closur
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We achieved efficient synthesis of imidazo- and pyrimido[1,2-b]benzo-1,2,4-thiadiazine-1,1-dioxides by the tandem aza-Wittig reaction/intramolecular NH-nucleophilic addition/NH-nucleophilic substitution cyclization methodology, involving sulfonamide ester
- Hirota, Shinsuke,Sakai, Terumi,Kitamura, Nobuhide,Kubokawa, Keisuke,Kutsumura, Noriki,Otani, Takashi,Saito, Takao
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experimental part
p. 653 - 662
(2010/09/05)
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- First total synthesis of (Z)-11-(2-oxopropylidene)-2,3,11,11a-tetrahydro- 1H-benzo[e]pyrrolo[1,2-a][1,4]diazepin-5(10H)-one
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The first total synthesis of naturally occurring (Z)-11-(2-oxopropylidene)- 2,3,11,11a-tetrahydro-1H-benzo[e]pyrrolo[1,2-a][1,4]diazepin-5(10H)-one,a unique cycloanthranilylproline derivative, has been achieved from readily available anthranilic acid in f
- More, Satish S.,Shanmughapriya,Lingam,Patel
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experimental part
p. 2058 - 2066
(2009/10/24)
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- Microwave-assisted base-catalyzed cyclization and nucleophilic substitution of o-azidobenzanilides to synthesize 1,2-disubstituted indazol-3-ones
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A series of 1,2-disubstituted indazol-3-ones were synthesized by microwave-assisted base-catalyzed cyclization and nucleophilic substitution of o-azidobenzanilides. Among five tested reaction conditions, the cyclization of o-azidobenzanilides catalyzed by
- Shaw, Arthur Y.,Chen, Yi-Ru,Tsai, Chia-Hua
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experimental part
p. 2647 - 2663
(2009/12/06)
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- ANALOGUES OF N-ACETYLARDEEMIN, METHOD OF PREPARATION AND USES THEREOF
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The present invention provides a compound having the structure: wherein R1 R6 and R7 are independently hydrogen, OH, NH2, SH, halogen, C1-C9 linear or branched chain alkyl, alkylmercapto, alkylamino, dialkylamino, alkoxy, phenyl, etc.; wherein R0 and R2 are independently hydrogen, OH, linear or branched chain alkyl, -CR3R3-CH(O)CH2, -CR3R3-CH2CH3, -CR3R3-CH2CH2OH, -CR3R3-CH(OH)R4 or -CR3R3-CH=CHR4; wherein R3 and R4 are independently hydrogen, halogen, C1-C9 linear or branched chain alkyl, phenyl, etc.; wherein R5 is hydrogen, C1-C9 linear or branched chain alkyl, phenyl, etc.; and wherein R8 is hydrogen, C1-C9 linear or branched chain acyl, benzoyl, etc.; with the proviso that (a) when R2 is -CR3R3-CH(O)CH2, -CR3R3-CH2CH3, -CR3R3-CH2CH2OH, -CR3R3-CH(OH)R4 or -CR3R3-CH=CHR4, then R2 is hydrogen; (b) when R0 is -CR3R3-CH(O)CH2, -CR3R3-CH2CH3, -CR3R3-CH2CH2OH, -CR3R3-CH(OH)R4 or -CR3R3-CH=CHR4, then R2 is OH; and (c) when (i) R0 or R2 is -CR3R3-CH=CHR4, (ii) R3 and R5 are CH3 and (iii) R4 is hydrogen, then R1, R6 and R7 are not all hydrogen. Also provided are related compounds and compositions, and methods of inhibiting the growth of multidrug resistant cells by means of MDR reversal, collateral sensitivity and quantitative synergism.
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Page/Page column 20
(2010/11/28)
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- Synthesis and evaluation of tricyclic pyrrolopyrimidinones as dipeptide mimetics: Inhibition of interleukin-1β-converting enzyme
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The application of a tricyclic pyrrolopyrimidinone scaffold for the synthesis of peptidomimetic inhibitors of interleukin-1β-converting enzyme (ICE) is reported. The synthesis of the tricyclic scaffold and conversion of it to a variety of target ICE inhib
- Laufersweiler, Michael C.,Wang, Yili,Soper, David L.,Suchanek, Maureen K.,Fancher, Amy N.,Lu, Wei,Wang, Richard L.,Oppong, Kofi A.,Ellis, Christopher D.,Baize, Mark W.,O'Neil, Steven V.,Wos, John A.,Demuth Jr., Thomas P.
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p. 4322 - 4326
(2007/10/03)
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- Ring closure to β-turn mimics via copper-catalyzed azide/alkyne cycloadditions
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Copper-catalyzed azide alkyne cycloadditions of the linear substrates 1 were used to form the cyclic derivatives 2. Computational, NMR, and CD analyses of these compounds indicate that their most favorable conformational states include type I and type II
- Angell, Yu,Burgess, Kevin
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p. 9595 - 9598
(2007/10/03)
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- Parallel fluorous biphasic synthesis of 3H-quinazolin-4-ones by an Aza-Wittig reaction employing perfluoroalkyl-tagged triphenylphosphine
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A perfluoroalkyl-tagged triphenylphosphine was applied in a fluorous biphasic system for the efficient parallel synthesis of 3H-quinazolin-4-ones via an Aza-Wittig reaction. The products were isolated by solid-phase extraction on fluorous reversed-phase silica gel. A new solid-phase bound phosphine derivative was used for comparison and yielded similar results.
- Barthélémy, Sophie,Schneider, Siegfried,Bannwarth, Willi
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p. 807 - 810
(2007/10/03)
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- A concise route to triazolobenzodiazepine derivatives via a one-pot alkyne-azide cycloaddition reaction.
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A new and efficient one-pot synthesis of [1,2,3]triazolo[1,5-a][1,4] benzodiazepin-6(4H)-ones is described starting from readily available anthranilic acids. A small array of the title compounds were assembled via a four-step sequence involving diazotisat
- Thomas, Andrew W
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p. 1881 - 1884
(2007/10/03)
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- Chemoenzymatic synthesis of pyrrolo[2,1-b]quinazolinones: Lipase-catalyzed resolution of vasicinone
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A facile synthesis of bronchodilatory pyrrolo[2,1-b]quinazoline alkaloids by azidoreductive cyclization strategy employing TMSCl-NaI and bakers' yeast is described. Both the chemical and enzymatic methods are mild and take place at room temperature in good yields. Further, synthesis and resolution of vasicinone has been carried out by employing different lipases. It has been observed that lipase PS provides acetate of (S)-vasicinone in 98% ee.
- Kamal,Ramana,Rao
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p. 997 - 1001
(2007/10/03)
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- Chemoselectivity in the intramolecular AZA-wittig reaction of N-[2-(trisubstituted phosphoranylidene)aminobenzoyl]-2-pyrrolidone-5-carboxylic acid derivatives
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The intramolecular aza-Wittig reaction of (5S)-N-[2-(trisubstituted phosphoranylidene)aminobenzoyl]-2-pyrrolidone-5-carboxylic acid derivatives gave chemoselectively pyrrolo[2,1-c][1,4]benzodiazepin derivatives or pyrrolo[2,1-b]quinazoline derivatives depending on their substituents and phosphorus reagent.
- Okawa, Tomohiro,Sugimori, Toshiyuki,Eguchi, Shoji,Kakehi, Akikazu
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p. 375 - 382
(2007/10/03)
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- Comparative study of synthetic approaches to 1- arylmethylenepyrazino[2,1-b]quinazoline-3,6-diones
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The transformation of 3-arylmethylenepiperazine-2,5-diones (1) into 1- arylmethylene-2,4-dihydro-1H-pyrazino[2,1-b]quinazoline-3,6-diones (2) was studied. Four synthetic methods were compared, namely direct condensation with the product of the reaction be
- Cledera, Pilar,Avendano, Carmen,Menendez, J. Carlos
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p. 12349 - 12360
(2007/10/03)
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- The first total synthesis of (-)-benzomalvin A and benzomalvin B via the intramolecular aza-Wittig reactions
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The first total synthesis of (-)-benzomalvin A, which possesses 4(3H)-quinazolinone and 1,4-benzodiazepin-5-one moieties, was described. Both of 6- and 7-membered ring skeletons were efficiently constructed by the intramolecular aza-Wittig reactions as th
- Sugimori, Toshiyuki,Okawa, Tomohiro,Eguchi, Shoji,Kakehi, Akikazu,Yashima, Eiji,Okamoto, Yoshio
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p. 7997 - 8008
(2007/10/03)
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- On the fate of the tryptophan stereocenter during the synthesis of hexacyclic analogues of N-acetylardeemin
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The reaction between 6-acetyl-3-alkyl-1-ethoxy-3,4,5a,6,11,11a- hexahydro-10bH-pyrazino-[2',1'-5,1]pyrrolo-[2,3-b]indole-1,4-diones and anthranilic acid was studied from a stereochemical point of view. Various degrees of epimerization of the tryptophan an
- Caballero, Esmeralda,Avendano, Carmen,Menendez, J. Carlos
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p. 3025 - 3038
(2007/10/03)
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- The synthesis of a novel benzodiazocine via an intramolecular Staudinger/aza-Wittig cyclization
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The novel pyrrolobenzodiazocine (1) has been prepared by an intramolecular Staudinger/aza Wittig protocol from the precursor azido aldehyde (2) in a remarkable 93% yield. Aldehyde (2) was prepared by coupling protected homoprolinol with 2-azidobenzoic aci
- O'Neil, Ian A.,Murray, Clare L.,Potter, Andrew J.,Kalindjian, S. Barret
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p. 3609 - 3610
(2007/10/03)
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- Tetrazolo[1,5-alquinolines and 1,2,3-triazolo[1,5-alquinazolines by the action of cyano-carbanions on 2-azidoarylcarbonyl compounds
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In protic solvents, 2-azidobenzaldehyde undergoes base-catalysed condensation with cyanocarbanions to yield tetrazolo[1,5-a]quinolines 5a-g, whereas in aprotic media 1,2,3-triazolo[1,5-a]quinazolines 6a-f are formed. Triazoloquinazolines 9 a-g are also ob
- Porter, Thomas C.,Smalley, Robert K.,Teguiche, Mabrouk,Purwono, Bambang
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p. 773 - 777
(2007/10/03)
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- Synthesis of optically active vasicinone based on intramolecular aza-Wittig reaction and asymmetric oxidation
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Both optical isomers of a quinazoline alkaloid, vasicinone, were synthesized by two different methods. The first method used (3S)-3-hydroxy-γ-lactam as a chiral synthon, which was, after O-TBDMS protection, o-azidobenzoylated followed by treatment with tri-n-butylphosphine to afford (S)-(-)-vasicinone via the tandem Staudinger/intramolecular aza-Wittig reaction. The second method utilized asymmetric oxygenation of deoxyvasicinone with (1S)-(+)- or (1R)-(-)-(10-camphorsulfonyl)oxaziridine (the Davis reagent), respectively. The aza-enolate anion of deoxyvasicinone was treated with (S)-(+)-reagent to afford (R)-(+)-vasicinone in 71% ee, while the reaction with (R)-(-)-reagent gave (S)-(-)-vasicinone in 62% ee. The optical purity was analyzed by HPLC on specially modified cellulose as a stationary phase. These results provided a facile method to prepare both optical isomers of vasicinone and confirmed the recently reversed stereochemistry of natural (-)-vasicinone.
- Eguchi, Shoji,Suzuki, Toshio,Okawa, Tomohiro,Matsushita, Yuji,Yashima, Eiji,Okamoto, Yoshio
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p. 7316 - 7319
(2007/10/03)
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- Photochemistry of 2-(methoxycarbonyl)phenyl azide studied by matrix-isolation spectroscopy. A new slippery energy surface for phenylnitrene
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Broad-band irradiation (λ > 350 nm) of 2-(methoxycarbonyl)phenyl azide (1) in Ar at 10 K monitored by IR and UV-vis spectroscopy resulted in the formation of at least five major products, all of which were shown to be photointerconvertible under these con
- Tomioka, Hideo,Ichikawa, Naoki,Komatsu, Kazunori
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p. 8621 - 8626
(2007/10/02)
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- Novel Ring Enlargement of Lactams via Quinazolinone Annelation. A Facile Route to Benzoannelated Large-Membered Cyclic 1,5-Diamines
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A novel route to benzoannelated large-membered cyclic 1,5-diamines from lactams is described.Thus, n-membered lactames 1 were N-acylated by o-azidobenzoyl chloride 5 to afford the corresponding imides 4.These were treated with tributylphosphine and underw
- Takeuchi, Hisato,Matsushita, Yuji,Eguchi, Shoji
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p. 1535 - 1537
(2007/10/02)
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- A NEW EFFICIENT SYNTHESIS OF IMIDAZOLINONES AND QUINAZOLINONE BY INTRAMOLECULAR AZA-WITTIG REACTION
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A new synthesis of imidazolinones and quinazolinones by intramolecular aza-Wittig reaction is described.Readily available azido substituted imides 4, 6, 10, and 12 reacted with triphenylphosphine or tributylphosphine to afford the corresponding imidazolin
- Takeuchi, Hisato,Hagiwara, Satoshi,Eguchi, Shoji
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p. 6375 - 6386
(2007/10/02)
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- Intramolecular 1,3-Dipolar Cycloadditions. Part 1. A Facile Synthesis of Benzimidazo- and Quinazolinotriazolobenzodiazepines
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The synthesis of hitherto unknown 9H-benzimidazotriazolobenzodiazepines (4, 11a-e and 12a-c) and 9H-quinazolinotriazolobenzodiazepin-11-ones (5 and 18a-g) is reported. 2-(2-Azidoaryl)benzimidazoles (6 and 10a-h) and 2-(2-azidoaryl)quinazolin-4(3H)-ones (7 and 17a-g) react with propargyl bromide to give non-isolable intermediates which undergo an intramolecular 1,3-dipolar cycloaddition to the title compounds.
- Mohiuddin, Ghulam,Reddy, Padala Satyanarayana,Ahmed, Khalil,Ratnam, Chengalvala Venkata
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p. 1839 - 1868
(2007/10/02)
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