bluuebunny/crossref_metadata_2025_split huggingface dataset:
The synthesis and transformations of 2‐[2‐ethoxycarbonyl‐2‐(2‐pyridinyl)ethenyl]amino‐3‐dimethylaminopropenoates. the synthesis of substituted β‐amino‐α,β‐didehydro‐a‐amino acid derivatives
Authors: Jukić Lucija , Rečnik Simon , Svete Jurij , Stanovnik Branko , Grdadolnik Simona GoliČ 
Published: March 2009

AbstractAlkyl (Z)‐2‐[(E)‐2‐ethoxycarbonyl‐2‐(2‐pyridinyl)ethenyl]amino‐3‐dimethylaminopropenoates 7 and 8 were prepared from ethyl 2‐pyridinylacetate (1) in two steps. Substitution of the dimethylamino group with alkyl‐, aryl‐, or heteroarylamines afforded the corresponding β‐alkyl‐ 22–24, β‐aryl‐ 25–35, and β‐herteroaryl‐amino‐α,β‐didehydro‐α‐amino acid 36 and 37 derivatives, intermediates for further preparation of various heterocyclic systems. The orientation around both double bonds were determined by various nmr techniques.
1H‐4,5,6,7‐Tetrahydro‐1,3‐diazepines. part II: basicity and hydrolysis of 1, 2‐diaryl derivatives
Authors: Hedrera Mónica E. , Perillo Isabel A. , Fernández Beatriz 
Published: March 2009

AbstractBasicity and alkaline hydrolysis of 1,2‐diaryl‐1H‐4,5,6,7‐tetrahydro‐1,3‐diazepines 1 are studied. Results are analyzed on the basis of Hammett and Swain‐Lupton constants, finding good structure‐basicity correlation when both, inductive and mesomeric effects, are considered together. Regioselectivity is observed in the alkaline hydrolysis of compounds 1, and it is analyzed in light of the stereoelectronic control theory. Results are compared with those previously obtained for five and six membered ring homologues: 1H‐4, 5‐dihydroimidazoles and 1,4,5,6‐tetrahydropyirimidines respectively.
Synthesis of bis‐heteroaryl piperazine derivatives as potential reverse transcriptase inhibitors
Authors: Guillaumel Jean , Grierson David S. , Monneret Claude 
Published: March 2009

AbstractVinylogous analogs of non‐nucleoside reverse transcriptase inhibitors belonging to the bis‐(hetero‐aryl)piperazine (BHAP) series were synthesized by coupling a piperazine derivative with (E)‐propenoyl derivatives of heterocyclic moieties.
Reactions of cyclic oxalyl compounds, 43: Synthesis and thermolysis of fused 1‐arylaminopyrrolones
Authors: Kollenz Gert , Theuer Ralph , Peters Karl , Peters Eva‐Maria 
Published: March 2009

AbstractFused N‐(di)arylamino‐pyrrol‐2,3‐diones 1 are reacted with diphenylketene, thiosemicarbazide or 1,2‐diaminobenzene to afford the 3‐diphenylmethylene pyrrolones 2, the thiosemicarbazones 4 or the quinoxaline derivatives 5 as well as 6, respectively. Thermolysis of 2b,c,e,f,6b and the pyrrolo‐quinoxaline 8 afford the corresponding N‐deaminated products 3, 7 and 9. Rearrangements into diazapropellanes following a thermally initiated Fischer ‐ indolization as originally expected do not occur.
Synthesis of η6‐(4a‐Methyl‐1,2,3,4‐tetrahydro‐4aH‐carbazole)‐tricarbonylchromium complex and stereoelectronic behaviour with organolithium reagents: an apparent frontal attack to the (CO)3Cr group
Authors: Rodríguez J. Gonzalo , Urrutia Anahí , Lafuente Antonio 
Published: March 2009

AbstractThe synthesis of η6‐(4a‐methyl‐1,2,3,4‐tetrahydro‐4aH‐carbazole)tricarbonylchromium (3) is described, and its reactivity with organolithium reagents have been analysed. The addition of RLi (R= H, Me, n‐Bu, tert‐Bu) to 3 affords the corresponding endo/exo tricarbonylchromium complexes of cis‐4a‐methyl‐9a‐substituted‐1,2,3,4‐tetrahydro‐4aH‐carbazole, which permit the consideration of the stereoelectronic behaviour of the tricarbonylchromium group on 4a‐methyl and the 9a substituent or on the methylenes of the cyclohexene moiety in the complexes.
An inexpensive, selective procedure for oxidizing α‐methyl to α‐formyl pyrroles pavel bobal
Authors: Lightner David A. 
Published: March 2009

Abstractα‐Methylpyrroles are converted to α‐formyl by sodium bromate in aqueous methanol in ∼60% yield. Adding 1% ceric ammonium nitrate as a co‐oxidant brings the isolated yields of synthetically useful 2‐formylpyrroles 2a‐d up to ∼70%, or close to those found when using only the considerably more expensive ceric ammonium nitrate as oxidant.
Ruthenium‐catalyzed synthesis of quinolines via reductive heteroannulation of nitroarenes with 3‐amino‐1‐propanols
Authors: Cho Chan Sik , Kim Tae Kyung , Kim Tae‐Jeong , Shim Sang Chul , Yoon Nam Sik 
Published: March 2009

AbstractNitroarenes are reductively cyclized with 3‐amino‐1‐propanols in dioxane/H2O in the presence of a ruthenium catalyst and tin(II) chloride dihydrate together with isopropanol to afford the corresponding quinolines. A reaction pathway involving initial reduction of nitroarenes to anilines, propanol group transfer from 3‐amino‐1‐propanols to anilines, N‐alkylation of anilines by 3‐anilino‐1‐propanols and heteroannulation of 1,3‐dianilinopropanes is proposed.
Novel synthesis of 3‐phenylazo‐1,5‐benzothiazepines, ‐1,5‐benzoxazepines and ‐1,5‐benzodiazepines via a one‐pot reaction
Authors: Abd El Latif Fawi M. , El‐Rady Eman A. , Khalil Mohamed A. , El‐Maghraby M. A. 
Published: March 2009

AbstractNovel polysubstituted ‐1,5‐benzothiazepine, ‐1,5‐benzoxazepine, and ‐1,5‐benzodiazepine were prepared in good yields by the reaction of hydrazono derivatives with o‐thioaminophenol, o‐aminophenol and o‐phenylenediamine via a one‐pot reaction.
Diastereoselective access to chiral non‐racemic [1,3]oxazolo‐[2,3‐a]isoindol‐5‐one ring systems viaO‐cationic cyclization
Authors: Sikoraiová Jana , Marchalín ŠTefan , Chihab‐Eddine Abderrahim , Daïch Adam 
Published: March 2009

AbstractDedicated to Professor Jean Morel for his retirementThe title compounds 4 have been prepared from suitable β‐amino‐ alcohol 2 and phthalic anhydride (5) in a three‐step sequence in moderate to good yields (58‐94%). The key step of this methodology is based on an intramolecular O‐cationic cyclization involving N‐acyliminium species. The high levels of the observed chemoselectivity during the intermolecular or intramolecular cyclization were also discussed.
Tin(II) chloride‐mediated synthesis of 2‐substituted benzoxazoles
Authors: Cho Chan Sik , Kim Dong Tak , Zhang Jiao Qiang , Ho Son‐Lam , Kim Tae‐Jeong , Shim Sang Chul 
Published: March 2009

Abstract2‐Aminophenols react with an array of carboxylic acids in dioxane at 180° in the presence of tin(II) chloride to afford the corresponding 2‐substituted benzoxazoles in good yields. The reaction is applicable to a wide range of alkyl, alkenyl, aryl carboxylic acids.
Synthesis and biological activities of quinolone analogues: Pyridazino[3,4‐b]quinoxalin‐4‐one
Authors: Kurasawa Yoshihisa , Kim Ho Sik 
Published: March 2009

AbstractQuinolone analogues I‐VI with pyridazino[3,4‐b]quinoxaline ring system were synthesized form the (l‐alkylhydrzino)quinoxalina N‐oxides 1 via oxidation of pyridazino[3,4‐b]quinoxalines 2,3,5,7, quinoxalino[2,3‐c]cinnolines 4, and 1,2‐dizepino[3,4‐b]quinoxalines 6. The biological activities of quinolone analogues IVa (N1‐methyl‐C3‐methyl), Va (N1‐methyl‐C3‐ethyl), and VI (N1‐methyl‐C3‐H) were superior to those of quinolone analogues I (N1‐ethyl‐C3‐carboxyl), 26b (N1‐ethyl‐C3‐carboxylate), and IIIc,d [N1‐alkyl‐C3‐(CH2)3COOC2H5].
Rearrangement of spiro[2H‐1‐benzopyran‐2,2′‐[2H]indoles] to pyrrolo[1,2‐a]indole derivatives
Authors: Martynaitis Vytas , Šačkus Algirdas , Berg Ulf 
Published: March 2009

AbstractHeating of 1′‐(N‐substituted carbamoyl)methylspiro[2H‐1‐benzopyran‐2,2′‐[2H]indoles] with potassium hydroxide in ethanol yields diastereomeric 5a,13‐methano‐6H‐1,3‐benzoxazepino[3,2‐a]indole‐12‐carbox‐amides. Reduction of the latter with sodium borohydride affords 1,2,3,9a‐tetrahydro‐2‐hydroxyaryl‐9H‐pyrrolo[ 1,2‐a] indole‐3 ‐carboxamides.
Derivatives of 5‐Oxy‐pyrido[2,3‐b]quinoxaline‐9‐carboxylic acid: A tricyclic system useful for the synthesis of potential intercalators
Authors: Varvaresou Athanasia , Iakovou Kriton 
Published: March 2009

AbstractThe synthesis of a new series of 5‐oxy‐pyrido[2,3‐b]quinoxaline‐9‐carboxamides 4a‐i and N1,N2‐Bis(5‐oxy‐pyrido[2,3‐b]quinoxaline‐9‐benzoyl)ethylenediamine (5) is reported starting from 2‐chloro‐3‐nitropyri‐dine. Fundamental steps of the synthetic pathway are i) preparation of 2‐(3‐nitro‐pyridin‐2‐ylamino)benzoic acid (1) via copper‐catalyzed condensation of 2‐chloro‐3‐nitropyridine with o‐anthranilic acid, ii) intramolecular cyclization of the acid 1 to 5‐oxy‐pyrido[2,3‐b]quinoxaline‐9‐carboxylic acid (2b) upon treatment with concentrated sulfuric acid and oleum and iii) conversion of the acid 2 to the desired amides 4a‐i and 5. Compounds 4a‐i and 5 are oxygenated azaanalogs of phenazines, a wellknown series of intercalators with cytotoxic activity.
Determination of aromaticity indices of thiophene and furan by nuclear magnetic resonance spectroscopic analysis of their anilides
Authors: Lee Chang Kiu , Yu Ji Sook , Ji Young Ran 
Published: March 2009

AbstractA series of m‐ and p‐substituted anilides of benzoic acid, 2‐thienoic acid, and 2‐furoic acid were prepared and their 1H and 13C nmr spectroscopic characteristics were examined. In general, good correlations were observed between the chemical shifts of proton and carbon signals of the acyl aromatic rings and the Hammett σ. Plots of the chemical shift values of the carbonyl carbons of the benzanilides against those of the 2‐thienamides and 2‐furamides gave an excellent correlation and the values of the slopes are 0.79 and 0.52, respectively, in dimethyl sulfoxide‐d6. The slopes could be considered as a set of aromaticity index.
Azinoiminophosphorane mediated synthesis of 5H, 7H‐1,2,4‐triazolo[1,5‐c][1,3]benzoxazepin‐7‐ones and 6H,8H‐1,2,4‐triazolo‐[1,5‐c][1,3]oxazepin‐6‐ones
Authors: Lee Chang Hoon , Kim Bong Gyu , Lee Kee‐Jung 
Published: March 2009

AbstractThe aza‐Wittig reactions of benzophenone‐, acetophenone‐ and benzaldehyde l‐[(triphenylphosphoranyl‐idene)amino]ethylidenehydrazones (4) with phthalic anhydride, 2,3‐dimethylmaleic anhydride and 7‐oxabi‐cyclo[2,2,l]hept‐5‐ene‐2,3‐dicarboxylic anhydride (5a) provide a new route to 5H,7H‐1,2,4‐triazolo[1,5‐c]‐[1,3]benzoxazepin‐7‐ones 8a‐c or 6H,8H‐1,2,4‐triazolo[1,5‐c][1,3]oxazepin‐6‐ones 8d‐h via the thermal reaction of the expected azinoimine lactones 6.
Synthesis of novel phenanthroline derivatives by 3+2 dipolar cycloadition reaction
Authors: Danac Ramona , Rotaru Alexandra , Drochioiu Gabi , Druta Ioan 
Published: March 2009

AbstractEleven new 1,10‐phenanthroline derivatives have been prepared by 3+2 dipolar cycloaddition reactions of 1,10‐phenanthrolinium‐ylides 7–12 in situ generated from corresponded salts, with dimethyl acetylene‐dicarboxylate and ethyl propiolate.
An efficient synthesis of 3‐hydroxychromone using niobium pentachloride
Authors: Constantino Mauricio Gomes , Júnior Valdemar Lacerda , Da Silva Gil Valdo José 
Published: March 2009

AbstractA new and efficient 2‐step synthesis of 3‐hydroxychromone is described. Commercially available chromone is converted to the corresponding epoxide which is rearranged with niobium pentachloride to 3‐hydroxychromone in 61% overall yield.
Reactions of o‐quinones with α‐methyl‐ (or methylene) substituted phosphorus ylides. Synthesis of benzo[b]furan derivatives
Authors: Gautam Daman R. , Litinas Konstantinos E. , Fylaktakidou Konstantina C. , Nicolaides Demetrios N. 
Published: March 2009

AbstractIn Wittig reaction of some α‐methyl‐ and α‐methylene‐substituted phosphorus ylides with o‐quinones, benzo[b]furan derivatives were obtained via the cyclization of the o‐vinylphenols, initially formed from the tautomerization of the corresponding intermediate o‐quinone methides.
Syntheses and properties of dithia‐tetrahomodiaza‐calix[4]arenes bridged by cystine unit
Authors: Ito Kazuaki , Suzuki Akane , Ito Naoto , Teraura Hiroyuki , Ohba Yoshihiro 
Published: March 2009

AbstractDithia‐tetrahomodiaza‐calix[4]arenes were synthesized by the cyclization reactions of bis(3‐(chloro‐methyl)‐2‐hydroxyphenyl)sulfide with cystine peptides in moderate yields. Conformational analysis of the macrocycles by using nmr spectroscopy reveled that the cyclophanes adopt a cone‐like form as a preferable conformation and the cystine bridge moiety is incorporated in the cavity. The calixarene analogs can extract transion metals such as Zn2+ and Cu2+ ions from an aqueous phase into chloroform.
Synthesis of heteroaryl substituted α‐mercapto acids from thiomalic acid using hexafluoroacetone as protecting and activating reagent
Authors: Pumpor Ksenia , Windeisen Elisabeth , Burger Klaus 
Published: March 2009

AbstractThe synthesis of heterocyclic α‐mercapto acids starting from (RS)‐thiomalic acid using hexafluoroacetone as protecting and activating agent is described. The new compounds are useful building blocks for peptide and depsipeptide modification as well as for drug design.
7‐Methyl Trimethoprim Analogues as Inhibitors of the Folate Metabolizing Enzymes
Authors: Gangjee Aleem , Lin Xin , Queener Sherry F. 
Published: March 2009

AbstractA series of 5‐(1‐phenylethyl)pyrimidines 2–10 (Table I) were designed and synthesized as potent and selective inhibitors of Pneumocystis carinii (P. carinii), Toxoplasma gondii (T. gondii) and Mycobacterium avium (M. avium) dihydrofolate reductases (DHFR). The structure of 2–10 incorporates a 7‐methyl group to increase the potency of monocyclic trimethoprim (TMP). The target compounds were synthesized by an acid catalyzed condensation of ethyl cyanoacetate and appropriately substituted benzaldehydes followed by a Michael addition using methyl copper‐lithium. The resulting adduct was cyclocondensed with guanidine to afford 2,6‐diamino‐4‐hydroxy‐5‐(1‐phenylethyl)pyrimidines 2–7. Both amino moieties of 2–4 were protected with pivaloyl groups and their 4‐hydroxy group chlorinated with phosphorus oxychloride. The resulting intermediates were subjected to hydrogenation and deprotection to afford 8–10. Compound 7 was a good inhibitor of DHFR, however the other compounds were poor inhibitors of P. carinii, T. gondii and M. avium DHFR.
Synthesis of N‐(Substituted aryl/cyclohexyl)‐N'‐[5‐bromo‐5‐nitro‐2‐oxido‐1,3,2‐dioxaphosphorinane‐2‐yl]ureas
Authors: Reddy P. Vasu Govardhana , Babu Y. Hari , Reddy C. Suresh 
Published: March 2009

AbstractN‐(Substituted aryl/cyclohexyl)‐N'‐[5‐bromo‐5‐nitro‐2‐oxido‐1,3,2‐dioxaphosphorinane‐2‐yl]ureas RR'P(O)NHC(O)NHR' (5) were synthesized by the reactions of 2‐bromo‐2‐nitro‐1,3‐propanediol (4) with chlorides of aryl/cyclohexyl carbamidophosphoric acids (3) in the presence of triethylamine at room temperature. Their ir, 1H, 13C and 31P nmr spectral data are discussed.
The reaction of acetic acid 2‐selenoxo‐2H‐pyridin‐1‐yl esters with benzynes: A convenient route to Benzo[b]seleno[2,3‐b]pyridines
Authors: Narasimha Rao U. , Sathunuru Ramadas , Maguire John. A. , Biehl Ed 
Published: March 2009

AbstractBenzyne and its 3,4,5,6‐tetraphenyl, 3‐ and 4‐methyl, 3‐methoxy and 4,5‐difluoro derivatives react with acetic acid 2‐selenoxo‐2H‐pyridin‐1‐yl esters 4a‐e to give benzo[b]seleno[2,3‐b]pyridines 10–15 in modest yields. The benzynes were generated by one or more of the following methods: diazotization of anthranilic acids 5a‐g with isoamyl nitrate; mild thermal decomposition of 2‐diazoniobenzenecarboxylate hydrochlorides 6a‐d treatment of (phenyl)[o‐(trimethylsilyl)phenyl]iodonium triflate (7) with tetrabutylammonium fluoride; and treatment of 2‐trimethylsilylphenyl triflates 8a‐c with cesium fluoride. In all the reactions, the corresponding 2‐(methylselenenyl)pyridines 16a‐d were also obtained suggesting that these reactions may involve selenium addition to benzyne via a SET (single electron transfer).
Simple and efficient cleavage reaction of the boc group in heterocyclic compounds
Authors: Nadia Klai , Malika Berredjem , Nawel Khettache , Yazid Belghit Med , Zine Régaïnia , Aouf Nour‐Eddine 
Published: March 2009

AbstractDedicated to the memory of Pr. Ladjama Daif A series of chiral cyclosulfamides have been synthesized by alkaline cyclisation starting from N‐benzoylamino acids (Ala, Val, Leu, Phe) derivatives and chlorosulfonyl isocyanate. A simplified and regioselective deprotection of the cyclic compounds (cyclosulfamides) containing the tert‐butyloxycarbonyl group (Boc) has been achieved in good yield by fusion under reduced pressure.
The synthesis of azoniadithia[6]helicenes
Authors: Sato Kiyoshi , Okazaki Shuichi , Yamagishi Takamichi , Arai Sadao 
Published: March 2009

AbstractA new short‐step synthesis of 8a‐azonia[6]helicene (1) and the novel dithieno derivatives (2 and 3) is described. Double photocyclization of 2,8‐distyrylquinolizinium salt (8) gave 1 in 35% yield. Similarly, 2,8‐bis[2‐(2‐thienyl)vinyl]‐ and 2,8‐bis[2‐(3‐thienyl)vinyl]‐quinolizinium salts (9 and 10) afforded new azonia[6]helicenes containing two thiophene rings at the ends of helix, that is 7a‐azonia‐3,12‐dithia[6]helicene (2) and 7a‐azonia‐1,14‐dithia[6]helicene (3), in 43 and 35% yields, respectively. The total assignment of their 1H‐ and 13C‐nmr spectra was performed by utilizing two‐dimensional and NOE nmr spectroscopic methods.
Synthesis of α‐alkylidene‐γ‐butyrolactones via Ring‐cleavage/recyclization of 2‐Amino‐4,5‐dihydro‐3‐furancarboxamides
Authors: Okabe Fumi , Tagawa Yoshinobu , Yamagata Kenji 
Published: March 2009

AbstractThe reactions of 2‐amino‐4,5‐dihydro‐3‐furancarboxarnides 1a,b with cyanomethylene compounds (such as alkyl cyanoacetates and malononitrile) gave the corresponding ring‐opened products 2a‐f. Compounds 2a‐d reacted with methanesulfonic acid to give the corresponding α‐alkylidene‐γ‐butyrolactones 3a‐d. On the other hand, treatment of 2e,f with methanesulfonic acid yielded 3‐pyridinecarbonitrile derivatives 4a,b.
Synthesis of six new 2‐Aryl‐N‐biphenyl benzimidazoles and crystal structure of methyl 4′ [(2‐p‐Chlorophenyl‐1H‐benzimidazole‐1‐yl)‐methyl]biphenyl‐2‐carboxylate
Authors: Zhiming Zhou , Weifa Yu , Jun Zhang , Congxuan Yu , Xinqi Zhao 
Published: March 2009

AbstractSix new 2‐aryl‐N‐biphenyl benzimidazoles were designed and synthesized, starting with O‐phenylenediamine and carboxylic acids via cyclization, followed by N‐alkylation. All new compounds were identified by H NMR, IR, MS spectra and elemental analysis. The crystal structure of methyl 4′‐[(2‐p‐chlorophenyl‐1H benzimidazole‐1‐yl)methyl]biphenyl‐2‐carboxylate (4f) was determined by single crystal X‐raydiffraction.
Photoaddition of thiocarboxylic acids to 2,3‐diallyltetraazathiapentalenes
Authors: Matsumura Noboru , Mori Osamu , Takeguchi Toshio , Okumura Yasuyuki , Mizuno Kazuhiko 
Published: March 2009

AbstractPhotoirradiation of acetone solutions of 2,3‐diallyl‐6,7‐dihydro‐5H‐2a‐thia(2a‐SIV)‐2,3,4a, 7a‐tetraazacyclopent[cd]indene‐ 1,4(2H,3H)‐dithione (1) in the presence of excess thioacetic acid and thiobenzoic acid afforded addition products, 2,3‐bis(3‐acetylthiopropyl)‐ and 2,3‐bis(3‐benzoylthiopropyl)‐6,7‐dihydro‐5H‐2a‐thia(2a‐SIV)2,3,4a, 7a‐tetraazacyclopent[cd]indene‐1,4(2H,3H)‐dithiones, respectively, in good yields. These photoaddition reactions were facilitated by the addition of oxygen.
Oxazoles formation during O‐alkylation of isonitroso‐naphthols. X‐ray structure of [1,2]naphthoquinone 1‐[O‐(4‐tert‐butyl‐benzyl)‐oxime] and 2‐(4‐tert‐butyl‐phenyl)napth[1,2‐d]oxazole
Authors: Astolfi Paola , Carloni Patricia , Castagna Riccardo , Greci Lucedio , Stipa Pierluigi , Rizzoli Corrado 
Published: March 2009

Abstract1‐Nitroso‐2‐naphthol and 2‐nitroso‐1‐naphthol, both in the isonitroso form, react with benzyl bromides in THF and in the presence of triethylamine affording, in low yields, the corresponding O‐benzyl oximes and 2‐aryl naphthoxazoles in a 1:1 ratio, approximately. The structures of O‐benzyl oximes and naphthoxazoles isolated have been determined by X‐ray analysis.
Synthesis of novel 4,5‐diazafluoren‐9‐one derivatives and theoretical study of 3+2 cycloaddition reactions
Authors: Danac Ramona , Druta Ioan , Rotaru Alexandru , Ghirvu Constantin , Constantinescu Mircea 
Published: March 2009

AbstractSome novel salts of 4,5‐diazafluoren‐9‐one N‐monosubstituted have been obtained by using Kröhnke method. The ability of 9‐oxo‐4,5‐diazafluorenium phenacylides (as 1,3‐dipoles) to react with activated symmetric dipolarophiles to give new heterocyclic compounds is presented. The new heterocyclic system of 10,10c‐diazacyclopenta[c]fluoren‐6‐one is illustrated by a series of derivatives. The cycloaddition reaction proceeds, according to the semiempirical study, via a concerted nonsynchronous mechanism.
The unexpected rearrangement of 1,5‐benzodiazepin‐2,4‐dione to a benzimidazol‐2‐one derivative during N,N'‐diglucosylation
Authors: Lakhrissi Brahim , Massoui Mohamed , Essassi El Mokhtar , Lequart Vincent , Joly Nicolas , Martin Patrick , Goethals Gérard 
Published: March 2009

AbstractReaction of 1,5‐benzodiazepin‐2,4‐dione with 3‐O‐substituted‐5,6‐anhydro‐1,2‐isopropylidene‐α‐D‐glucofuranose gave the unexpected N,N'‐di‐glucofuranosyl benzimidazol‐2‐one by a novel rearrangement and ring closure reaction. A mechanism is proposed.
Strongly fluorescent dipyrrinones—substituent effects
Authors: Boiadjiev Stefan E. , Lightner David A. 
Published: March 2009

AbstractBright yellow N,N'‐carbonyl‐bridged dipyrrinones (substituted 3H,5H‐dipyrrolo[1,2‐c:2′,1′‐f]pyrimidine‐3,5‐diones) were synthesized by reaction of the parent dipyrrinone with carbonyldiimidazole. Their solutions in organic solvents fluoresced strongly, with fluorescent quantum yields (ϕF)0.32‐0.92.
Biomimetic processes. IV. Carbocationic polymerization of isoprene initiated by dimethyl allyl alcohol
Authors: Puskas Judit E. , Peres Clément , Peruch Frédéric , Deffieux Alain , Dabney David E. , Wesdemiotis Chrys , Hayat‐Soytaş Serap , Lindsay Allia 
Published: March 2009

AbstractIn this article, we investigate a new bio‐inspired synthetic route towards NR homologs based on the carbocationic polymerization of isoprene initiated by dimethyl allyl alcohol (DMAOH)/TiCl4 or BF3.Et2O as the catalytic system. This study is the continuation of our studies related to the proof of principle that NR biosynthesis is based on a carbocationic mechanism. It is shown that using the biomimetic strategy of initiation by allylic carbocations, polyisoprene carrying a dimethyl allyl head group is produced almost exclusively via 1,4 addition, yielding repeating units with cis and trans configurations. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2181–2189, 2009