bluuebunny/crossref_metadata_2025_split huggingface dataset:
“Azaphilic addition” of methyl lithium to 3,6‐bisalkylthio‐1,2,4,5‐tetrazines: A remarkable dichotomy
Authors: Wilkes Marty C. 
Published: March 2009

AbstractA new type of “azaphilic addition” reaction of methyl lithium to 3,6‐bisalkylthio‐1,2,4,5‐tetrazines has been discovered. Methyl lithium adds at the tetrazine nitrogen of 1 affording 4 while nitrogen nucleophiles displace tetrazine alkylthio groups at carbon affording 3. The structures of the N‐alkyl products were determined by 1H‐ and 13C‐nmr and uv experiments. Reversing the order of methyl lithium addition caused the formation of a bicyclic tetrazine 6. Grignard reagents add in the same fashion as methyl lithium.
Protonation studies on the oximes of some 7‐acetyl‐1,2‐benzisothiazoles
Authors: Mckinnon David M. , Abouzeid Azza A. 
Published: March 2009

AbstractThree 7‐acetyl‐1,2‐benzisothiazoles have been made by cyclisation of the monooximes of 2‐methylthio‐1,3‐diacetylbenzenes. The oximes of these ketones dissolved in acidic media give only protonated forms, and no indication of the formation of stable bridged sulfonium ions.
Carbamoylation of B6 vitamins
Authors: Ponticelli Fabio , Marinello Enrico , Pagani Roberto , Terzuoli Lucia 
Published: March 2009

AbstractThe reaction of B6 vitamins 1–3 with cyanate, in the presence of equivalent amounts of hydrochloric acid, yields different adducts according to the structure of the starting material. Regiospecific attack on the amino group or the phenolic hydroxy group was found for 2a,b and 3a,b, respectively. From the aldehydes 1a,b, the 2H‐pyrido[3,4‐e]‐1,3‐oxazin‐2‐ones 7a,b were obtained through an attack on both the phenolic and aldehyde group.
The synthesis of substituted [1]benzothieno[2,3‐c]quinolines and their N‐methyl quaternary salts
Authors: Luo Jiann‐Kuan , Musmar M. J. , Castle Raymond N. 
Published: March 2009

AbstractFour substituted [1]benzothieno[2,3‐c]quinolines 14a‐14d were prepared by photocyclization of the appropriate carboxamides 8a‐8d to the corresponding [1]benzothieno[2,3‐c]quinolin‐6(5H)‐ones 12a‐12d followed by chlorination to 6‐chloro[1]benzothieno[2,3‐c]quinolines 13a‐13d and dechlorination resulting in the title compounds. Treatment of 14a‐14d with iodomethane furnished the corresponding N‐methyl quaternary salts 5a‐5d.
Aziridination of the uracil 5,6‐olefinic bond of 3‐N‐3′,5′‐Di‐O‐tribenzoyl‐5‐vinyl‐2′‐deoxyuridine
Authors: Kumar Rakesh , Wiebe Leonard I. , Knaus Edward E. , Nakashima Thomas T. 
Published: March 2009

AbstractOxidation of N‐aminophthalimide with lead tetra‐acetate at ‐50° gives N‐acetoxyaminophthalimide (3) which selectively aziridinates the 5,6‐double bond present in 3‐N‐3′,5′‐di‐O‐tribenzoyl‐5‐vinyl‐2′‐deoxyuridine (1a) to yield 2‐[1′‐(2′‐deoxy‐β‐D‐ribofuranosyl)]‐7‐(1‐phthalimido)‐4‐N‐3′,5′‐di‐O‐tribenzoyl‐6‐vinyl‐2,4,7‐triazabicyclo[4.1.0]heptan‐3,5‐dione (5).
Formation of a 1,4,2,3‐dithiadiazine via dimerization of a transient thione‐S‐imide (thiocarbonyl imine dipole)
Authors: Potts Kevin T. , Baum Jonathan S. 
Published: March 2009

AbstractN‐(p‐Tolyl)trichloromethane sulfenamide when treated with potassium hydroxide in an ether‐alcohol mixture resulted in the formation in solution of a red, transient thione‐S‐imide which underwent a head‐to‐head dimerization to 2,3‐di(p‐tolyl)‐5,5,6,6‐tetrachloro‐1,4,2,3‐dithiadiazine whose structure was established by a single crystal X‐ray determination. A variety of sulfenamides derived from aryl‐substituted primary aromatic amines and alcoholic potassium hydroxide undergo this reaction with the formation of analogous structures. This thiocarbonyl imine dipole could not be trapped with alkenic or alkynic dipolarophiles.
Synthesis of 4,8‐disubstituted 4H,8H‐bis[1,2,5]oxadiazolo[3,4–6:3′,4′‐e]pyrazines
Authors: Fischer John W. , Nissan Robin A. , Lowe‐Ma Charlotte K. 
Published: March 2009

AbstractThe dilithio anion of 3,4‐N,N′‐disubstituted diamino[1,2,5]oxadiazole (4a R = benzyl, 4b R = p‐methoxybenzyl, 4c R = isopropyl) and cyanogen oxide gave 4,7‐disubstituted 5,6‐dioximino[1,2,5]oxadiazolo[3,4‐b]‐pyrazines 5a,b,c. Ring closure to the title compound 1 was accomplished upon heating 5 with sodium hydroxide in ethylene glycol at 150°.
Transformations of 2,2,6‐trimethyl‐1,3‐dioxen‐4‐one with heterocyclic amines and other amino compounds
Authors: Zupet Rok , Tišler Miha , Golič Ljubo 
Published: March 2009

AbstractHeterocyclic amines were acetoacetylated with 2,2,6‐trimethyl‐1,3‐dioxen‐4‐one and the obtained compounds reacted on the reactive methylene group to give C‐substituted products. Nitrosation, followed by reduction afforded a pyrazine derivative. Azido‐ or chloroacetamide were also acetoacetylated, with heterocyclic amines, the corresponding enamines were prepared and reduction of the azido group of 15 afforded compounds 22 and/or amides of substituted 3‐oxobutanoic acid 23. An X‐ray structural determination of compound 23a revealed that the orientation about the double bond is Z.
Alkylation of N‐boc‐1,2,3,4‐tetrahydroisoquinolines in the 1‐position and its application to the synthesis of isoquinoline alkaloids
Authors: Coppola Gary M. 
Published: March 2009

AbstractBoc‐protected 1,2,3,4‐tetrahydroisoquinolines 2 can be lithiated with t‐butyllithium in the presence of N,N,N',N',‐tetramethylethylenediamine. Reaction of the anion with alkyl halides provides 1‐alkyl N‐Boc‐1,2,3,4‐tetrahydroisoquinolines in 67–71% yield. The protecting group is easily removed in high yield with trifluoroacetic acid. The alkaloids salsolidine (8) and laudanosine (11) were synthesized in racemic form using this method.
Reissert compound studies. LXIV. Reissert compound and other products from an isolated N‐benzoylisoquinolinium triflate salt
Authors: Duarte F. F. , Popp F. D. 
Published: March 2009

AbstractIn the presence of trimethylsilyl trifluoromethanesulfonate, a methylene chloride solution of isoquinoline and benzoyl chloride gave N‐benzoylisoquinolinium triflate (3) and N‐H‐isoquinolinium triflate (4). Depending on the reaction conditions, reaction of 3 may occur on the isoquinoline ring yielding a Reissert compound and 1,2‐dihydroisoquinoline species. Otherwise, reactions transpire on the carbonyl of 3 to give an amide, an ester, and an anhydride.
The synthesis and biological activity of new 7‐[2‐(cyanomethyl)piperazinyl]‐ and 7‐[3‐(cyanomethyl)piperazinyl]quinolone antibacterials
Authors: Gubert S. , Braojos C. , Anglada L. , Bolós J. , Palacin C. 
Published: March 2009

AbstractSome novel 7‐[2‐ or 3‐(cyanomethyl)piperazinyl]quinolones have been prepared. Most notable, 2‐cyanomethyl‐piperazine 5 and 1‐methyl‐2‐cyanomethylpiperazine 8 at the quinolone C‐7 position produce products with good in vitro antibacterial activity. The key step in the synthesis of these products involves the regioselective deprotection of the benzyl group in function of the time reaction.
Multiple reactivity of freund's “methyl isothiocyanate sulfide” in cycloaddition‐elimination reactions
Authors: L'Abbé Gerrit , Sannen Ingrid , Vandendriessche Ann 
Published: March 2009

Abstract4‐Methyl‐5‐methylimino‐1,2,4‐dithiazolidine‐3‐thione (l)and 2,4‐dimethyl‐1,2,4‐thiadiazolidine‐3,5‐dithione (2) are interconvertible in acetone at 50°. They react with ketenes and electrophilic acetylenes to give the thiazole derivatives 6 and 7 after elimination of methyl isothiocyanate or carbon disulfide. Electrophilic isothiocyanates and phenylsulfonyl isocyanate transform the C = S function of 1 in an imine function (8), and a similar transformation of the thiourea C = S function of 2 is observed on reaction with phenylsulfonyl isocyanate, giving 9.
Substituted 1,4‐diazepino[5,6,7‐kl]acridines as unexpected side products in reaction of 2‐(dialkylamino)ethylamine with 1‐chloro‐7‐methyoxy‐4‐nitro‐9‐phenoxyacridine
Authors: Cholody Wieslaw M. , Martelli Sante , Gariboldi Pierluigi V. 
Published: March 2009

AbstractSubstituted 1,4‐diazepino[5,6,7‐kl]acridines were obtained in reaction of 2‐(dialkylamino)ethylamine with 1‐chloro‐7‐methoxy‐4‐nitro‐9‐phenoxyacridine. The mechanism of their formation was studied. The correct structure of these compounds was established on the basis of their 1H nmr studies.
N‐1 and C‐2 substituted tryptophans as potential inhibitors of sickle cell hemoglobin gelation
Authors: Prasitpan Noojaree , Patel Jayeshkumar N. , De Croos Philomen Z. , Stockwell Brenda L. , Manavalan Parthasarathy , Kar Leela , Johnson Michael E. , Currie Bruce L. 
Published: March 2009

AbstractA series of N‐1 or C‐2 phenylalkyl substituted tryptophans and C‐1 phenylalkyl substituted 3,4‐dihydro‐β‐carbolines were prepared from the apropriate aniline, 1b or 1e, or tryptophan, 8 or 11, by ring closure methods. None of the compounds prepared were more potent than 5‐bromotryptophan (11) as inhibitors of sickle cell hemoglobin gelation.
Novel transformations of two kinds of chlorinated photo [2 + 2] cycloadducts of 2‐pyrone‐5‐carboxylate
Authors: Shimo Tetsuro , Date Kenichi , Somekawa Kenichi 
Published: March 2009

AbstractNovel reactions of 7,7‐dichloro‐ and 7,7,8‐trichloro‐3‐oxo‐2‐oxabicyclo[4.2.0]oct‐4‐ene‐6‐carboxylates 5 with 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) in alcohol gave pyrano[4,3‐b]pyran‐2,5‐diones 8 via (Z)‐(2H‐pyran‐2‐on‐3‐yl)butenoates 7. On the other hand, the same treatment of 7,7,8‐trichloro‐2‐oxo‐3‐oxabicyclo‐[4.2.0]oct‐4‐ene‐5‐carboxylate 6b afforded 2‐oxo‐3‐oxabicyclo[4.2.0]oct‐4,7‐diene‐5‐carboxylate 14 via cyclobutene formation and SN2′ displacement by attack of the alkoxy anion.
The molecular structure of 2‐methylbenzotriazole (2MeBzTr) in connection with the x‐ray structure of 2MeBzTr.HBF4.H2O
Authors: Angeles Monge María , Gutiérrez Puebla Enrique , Ramos Gallego María Del Mar , Pardo Carmen , Elguero José 
Published: March 2009

AbstractThe fluoroborate of 1H‐2‐methylbenzotriazolium monohydrate crystallizes in the Pbca space group [Z = 8, a = 16.734(3), b = 19.153(9), c = 6.937(1) Å], The hydrogen bond network between the three molecules, 2MeBzTr, HBF4 and H2O, corresponds to a situation intermediate between the fluoroborate of a protonated benzotriazole (BF4−.2MeBzTrH+) and a neutral benzotriazole hydrogen‐bonded to fluoroboric acid (HBF4,2MeBzTr). The behaviour of the title compound in solution is also intermediate between these two extreme situations. Thus, the present compound is one of the rare examples of a proton solvated only by very weak hydrogen bond acceptors.
Synthesis of 3‐(6‐alkylaminopurin‐9‐yl)‐2,3‐dideoxy‐D‐thero‐pentopyranoses and their reduction to 3‐(6‐alkylaminopurin‐9‐yl)‐2,3‐dideoxy‐D‐thero‐pentitols
Authors: Hjuler‐Nielsen Hans Peter , Pedersen Hans , Hansen Henning Bue , Pedersen Erik B. , Nielsen Claus 
Published: March 2009

Abstract3‐(6‐Alkylaminopurin‐9‐yl)‐2,3‐dideoxy‐D‐threo‐pentopyranoses 3 were prepared by condensation of unprotected 2‐deoxy‐D‐ribose (2) with N6‐alkyladenines 1 in a phosphorus pentoxide reagent mixture. Reduction of the pentoses 3 gave the corresponding 3‐(6‐alkylaminopurin‐9‐yl)‐2,3‐dideoxy‐D‐threo‐pentitols 4. The structures of 3 and 4 were determined by 13C nmr, 1H nmr and 2D 1H nmr (COSY).
Synthesis of 6R(β)‐tritylaminopenicillanic‐3R(β)‐alcohol, a versatile stereoisomer of natural β‐lactams
Authors: De Meester F. , Frère J. M. , Piette J. L. , Jacquemin P. , Grooters L. , Llabres G. , Defays S. 
Published: March 2009

AbstractIn an attempt to rationalize a synthesis of penicillin analogs modified at C(3), we have isolated the 3R(β)‐carbinolamide derivative 4a. The trityl substituent on N(6′) seems to be responsible for the inversion of configuration which occurs at C(3) during the acid hydrolysis of the isocyanate intermediate. An hydrogen bond is formed on the β‐face of the bell‐shaped bicyclic skeleton between the N(6′)‐nitrogen lone pair and the C(3) hydroxyl group. On standing, the carbinolamide analog slowly isomerizes to its expanded bicyclic isomer 4b, but the starting material may be easily recovered by treatment with acid. The postulated intermediate during isomerization, i.e., the open aldehyde form, does not accumulate. Substitutions of the hydroxyl group at C(3) lead to a variety of compounds with the biologically active 3S(α) configuration. These may be used to study the importance of the carboxyl group of penicillins in their interaction with β‐lactamases at the molecular level.
Nitrogen bridgehead compounds. Part 83. Synthesis and ring transformation of 6‐methyl‐4‐oxo‐4H‐pyrido[1,2‐a]pyrimidine‐3‐acrylates
Authors: Hermecz István , Horváth Agnes 
Published: March 2009

AbstractThe thermal ring transformation of 2‐substituted 4‐oxo‐4H‐pyrido[1,2‐a]pyrimidine‐3‐acrylates gave 2‐substituted 1,8‐naphthyridine‐3‐acrylates, pyrano‐1,8‐naphthyridines and anthyridine, depending upon the nature of the 2‐substituent. A longer reaction period and a higher reaction temperature favored the formation of tricyclic products from 1,8‐naphthyridine‐3‐acrylate after isomerization of the side‐chain at position 3. The products were characterized by means of uv, ir and 1H nmr spectroscopy.
On the synthesis of 3,4‐dihydro‐2H‐1,2‐benzothiazine 1,1‐dioxides
Authors: Camoutsis Charalambos , Catsoulacos Panayotis 
Published: March 2009

AbstractThe 3,4‐dihydro‐2H‐1,2‐benzothiazine 1,1‐dioxides were prepared by reduction of the corresponding 1,2‐benzothiazin‐2‐ones with diborane. The latter were obtained by the action of primary amines on 4,5‐dimethoxy‐2‐carbomethoxymethylbenzenesulfonyl chloride followed by basic hydrolysis and cyclization of the formed 4,5‐dimethoxy‐2‐carbomethoxymethylbenezenesulfonamides.
Photochemistry of azole N‐oxides. Facile photoisomerisation of 2H‐imidazole N‐oxides to 1,3‐diaza‐6‐oxabicyclo[3.1.0]hex‐3‐enes and synthesis of a 1,3‐diaza‐4,7‐dioxatricyclo[4.1.0.1,603,5]heptane
Authors: Gainsford Graeme J. , Woolhouse Anthony D. 
Published: March 2009

AbstractUltraviolet irradiation of a series of 2H‐imidazole N‐oxides 2 has been shown to effect a clean isomerisation to derivatives of the new ring system, 1,3‐diaza‐6‐oxabicyclo[3.1.0]hex‐3‐ene, 7. Epoxidation of a representative 7 has given access to the hitherto inaccessible trans‐fused 1,3‐diaza‐4,7‐dioxatricyclo[4.1.0. 1,603,5]‐heptane ring system 9.
Diels‐alder reactions of 2‐pyrones with acyclic dienophiles and hydrolyses of the mono‐adducts
Authors: Shimo Tetsuro , Kataoka Katsuyuki , Maeda Ayumi , Somekawa Kenichi 
Published: March 2009

AbstractDiels‐Alder reactions of 2‐pyrone (1) with fumaronitrile and maleonitrile afforded regio‐ and stereo‐specific mono‐adducts 3a and 3b, respectively. The reaction of 1 with acrylonitrile gave a bis‐adduct. The reaction of 4,6‐dimethyl‐2‐pyrone (7) with dimethyl fumarate and dimethyl maleate at higher temperature gave benzene derivatives. The low reactivity of 7 and the instability of the mono‐adducts with 7 were considered from the existence of back reaction and easy elimination of methyl formate, respectively. Hydrolyses of the mono‐adducts of 2‐pyrones gave polyfunctionalized cyclohexenes and elimination products generated from the preferencial trans‐elimination of the leaving groups.
Preparation of bis(heteroaryl)iodonium salts via an iodonium transfer reaction between di(cyano)iodonium triflate and organostannes
Authors: Stang Peter J. , Tykwinski Rik , Zhdankin Viktor V. 
Published: March 2009

AbstractDi(cyano)iodonium triflate 5 generated in situ from iodosyl triflate (0 = I‐OTf) and cyanotrimethylsilane is a preferred reagent for the preparation of various bis(heteroaryl)iodonium triflate salts 11–15 via an iodonium transfer reaction with the corresponding tributyltin substituted heterocycles 6–10. Novel heteroaromatic iodonium salts 3, 11–15 were isolated in good yields as relatively stable microcrystalline solids and characterized by multinuclear nmr, ir and hrms data.
Study of the reactivity of ketone enolates with 3‐halo‐2‐amino derivatives of benzo[b]thiophene under photostimulated sRN1 reaction conditions
Authors: Beltran Lluís , Gálvez Carmen , Prats Montserrat , Salgado Juan 
Published: March 2009

AbstractReactivity of the 3‐halo‐2‐amino derivatives of benzo[6]thiophene 1a‐c and 2 with several ketone enolates 3–5 have been studied under photostimulated SRN1 reaction conditions. The normal substitution product 6 only was obtained in low yields using potassioacetophenone 3 as the enolate ion and 2‐(tert‐butoxycarbonylamino)‐3‐chlorobenzo[b]thiophene (1a) and 2‐(tert‐butoxycarbonylamino)‐3‐iodobenzo[b]thiophene (1c) as substrates. In all reactions the main product was the corresponding dehalogenated substrate 7a‐b, thus indicating that reduction of the substrate strongly competes with the desired substitution reaction.
Preparation of 6‐(nitron‐c‐yl)‐ and 6‐(1,3‐butadienyl)‐2‐pyrones and their cycloaddition reactions
Authors: Shimo Tetsuro , Somekawa Kenichi , Tsuge Otohiko 
Published: March 2009

Abstract6‐(N‐Substituted nitron‐C‐yl)‐2‐pyrones 1 and 6‐(4‐substituted 1,3‐butadienyl)‐2‐pyrone 2 were prepared and their cycloaddition reactions with three kinds of diene systems were investigated. Namely, the reactions of 1 with methyl acrylate, vinyl crotonate and divinylsulfone took place at the nitrone moiety to afford 3‐substituted isoxazolidines 9–14, and that of 2 with maleimide took place at the 2‐pyrone moiety to give a bis‐adduct 17 via elimination of carbon dioxide.
A facile synthesis of 3‐substituted indoles
Authors: Nagarathnam Dhanapalan 
Published: March 2009

Abstract1‐Benzoyl‐3‐bromomethylindole (2a) or 1‐benzenesulfonyl‐3‐bromomethylindole (2b) reacts with C, N, O, and P‐containing nucleophiles to give potential intermediates for the synthesis of a wide range of indole alkaloids and pharmacologically important substances, in good to excellent yields.
Preparation of benzo[c][2,7]naphthyridines
Authors: Nutaitis Charles F. , Marsh Stephen R. 
Published: March 2009

AbstractA divergent synthesis of substituted benzo[c][2,7]naphthyridines 5a‐h is described, which features an intramolecular pyridyne cyclization step as the key reaction. The pyridyne precursors are conveniently prepared from the pyridinium hydrochloride 2 and the requisite anilines. Cyclization of the non‐symmetric substrates 3e and 3f did not proceed with significant regioselectivity.
Synthesis, purification and spectroscopic characterization of potential impurities of hexamethylmelamine
Authors: Talebian Abdolhassen , Ghiorghis Alem , Hammer Charles F. , Murril Evelyn A. , Pallas Frank 
Published: March 2009

AbstractThe syntheses and spectroscopic properties (ir, 1H nmr, 13C nmr, uv and ms) of pure samples of 2‐chloro‐4,6‐bis(dimethylamino)‐s‐triazine 1, 4,6‐dichloro‐2‐dimethylamino‐s‐triazine 2, 4,6‐bis(dimethylamino)‐s‐triazin‐2(lH)‐one 3, 4‐chloro‐6‐dimethylamino‐s‐triazin‐2(1H)‐one 4, 6‐dimethylamino‐s‐triazine‐2,4(1H,3H)‐dione 5, and 2,4,6‐tris(dimethylamino)‐s‐triazine (altretamine, HMM) are reported. Evidence for enol‐keto equilibria are also presented for 3, in which the enol form exhibits as an H‐bonded dimer structure similar to the dimer of organic carboxylic acids.
A new synthetic route to 1,3,4‐oxadiazoles. Pharmacological study of some new derivatives
Authors: Reynaud Pierre , El Hamad Youssef , Davrinche Catherine , Nguyen‐Tri‐Xuong Emmanuel , Tran Gilles , Rinjard Pierre 
Published: March 2009

Abstract2‐Substituted 1,3,4‐oxadiazoles have been examined as possible prodrugs of antidepressant hydrazides. A new method of synthesis of this heterocycle from thionoester and five new oxadiazoles substituted at the 2‐position by a 4‐pyridyl or 4‐aminophenyl group and at the 5‐position by a phenyl group are described.
Synthesis of new 3‐(phenoxyphenyl)sydnones marija Šindler‐kulyk
Authors: Jakopčić Krešimir , Mance Ana Dunja 
Published: March 2009

AbstractThe title compounds were prepared by dehydrocyclization of corresponding substituted N‐nitrosoglycines obtained from isomeric o‐, m‐ and p‐aminodiphenyl ether with ethyl bromoacetate and subsequent nitrosation of the intermediate N‐arylsubstituted glycines.
Synthesis of 1,2‐diazepino[3,4‐b]quinoxalines and pyrido[3′,4′:9,8][1,5,6]oxadiazonino[3,4‐b]quinoxalines via a 1,3‐dipolar cycloaddition reaction
Authors: Kurasawa Yoshihisa , Kureyama Tomomi , Yoshishiba Noriko , Katoh Ritsuko , Takada Atsushi , Kim Ho Sik , Okamoto Yoshihisa 
Published: March 2009

AbstractThe reaction of 6‐chloro‐2‐(1‐methylhydrazino)quinoxaline 4‐oxide 8 with furfural, 3‐methyl‐2‐thiophene‐carbaldehyde, 2‐pyrrolecarbaldehyde, 4‐pyridinecarbaldehyde and pyridoxal hydrochloride gave 6‐chloro‐2‐[2‐(2‐furylmethylene)‐1‐methylhydrazino]quinoxaline 4‐oxide 5a, 6‐chloro‐2‐[1‐methyl‐2‐(3‐methyl‐2‐thienyl‐methylene)hydrazino]quinoxaline 4‐oxide 5b, 6‐chloro‐2‐[1‐methyl‐2‐(2‐pyrrolylmethylene)hydrazino]quinoxa‐line 4‐oxide 5c, 6‐chloro‐2‐[1‐methyl‐2‐(4‐pyridylmethylene)hydrazino]quinoxaline 4‐oxide 5d and 6‐chloro‐2‐[2‐(3‐hydroxy‐5‐hydroxymethyl‐2‐methyl‐4‐pyridylmethylene)‐1‐methylhydrazino]quinoxalme 4‐oxide 5e, respectively. The reaction of compound 5a or 5b with 2‐chloroacrylonitrile afforded 8‐chloro‐3‐(2‐furyl)‐4‐hydroxy‐1‐methyl‐2,3‐dihydro‐1H‐1,2‐diazepino[3,4‐b]quinoxaline‐5‐carbonitrile 6a or 8‐chloro‐4‐hydroxy‐1‐methyl‐3‐(3‐methyl‐2‐thienyl)‐2,3‐dihydro‐1H‐1,2‐diazepino[3,4‐b]quinoxaline‐5‐carbonitrile 6b, respectively, while the reaction of compound 5e with 2‐chloroacrylonitrile furnished 11‐chloro‐7,13‐dihydro‐4‐hydroxy‐methyl‐5,14‐methano‐1,7‐dimethyl‐16‐oxopyrido[3′,4′:9,8][1,5,6]oxadiazonino[3,4‐b]quinoxaline 7.
A convenient synthesis of cis‐4‐(sulfomethyl)‐piperidine‐2‐carboxylic acid: NMR assignment
Authors: El Hadri Ahmed , Leclerc GÉRard 
Published: March 2009

Abstractcis‐4‐(Sulfomethyl)piperidine‐2‐carboxylic acid was obtained in 22% overall yield from 4‐(hydroxymethyl)‐pyridine via the o‐silyl N‐oxide and trimethylsilylcyanide. The cis configuration of 5 was unambiguously assigned by 200 MHz 1H nmr and cosy experiments.
A facile synthesis of enol type acyl cyanides via a 1,3‐dipolar cycloaddition reaction and a cyano group migration
Authors: Kurasawa Yoshihisa , Kureyama Tomomi , Yoshishiba Noriko , Okano Tomoko , Takada Atsushi , Kim Ho Sik , Okamoto Yoshihisa 
Published: March 2009

AbstractThe reaction of 7‐chlorotetrazolo[1,5‐a]quinoxaline 5‐oxide 4a or 7‐chloro‐1,2,4‐triazolo[4,3‐a]quinoxaline 5‐oxide 4b with 2‐chloroacrylonitrile gave 7‐chloro‐4‐(2‐cyano‐2‐hydroxyvinyl)tetrazolo[1,5‐a]quinoxaline 5a or 7‐chloro‐4‐(2‐cyano‐2‐hydroxyvinyl)‐1,2,4‐triazolo[4,3‐a]quinoxaline 5b, respectively. Alcoholysis of compound 5a or 5b afforded 7‐chloro‐4‐ethoxycarbonylmethylene‐4,5‐dihydrotetrazolo[1,5‐a]quinoxaline 6a or 7‐chloro‐4‐ethoxycarbonylmethylene‐4,5‐dihydro‐1,2,4‐triazolo[4,3‐a]quinoxaline 6b, respectively. Compounds 5a,b were found to exist as a syn and anti mixture of the enol form, while compounds 6a,b occurred as the enamine and methylene imine forms. The tautoraeric character and/or D‐H exchange of the vinyl protons are described for compounds 5a,b and 6a,b.
A new class of laser dyes from acridinedione derivatives
Authors: Shanmugasundaram Palanisamy , Prabahar K. Joseph , Ramakrishnan Vayalakkavoor T. 
Published: March 2009

AbstractSynthesis of 10‐aryl‐3,4,6,7,9,10‐hexahydro‐1,8(2H,5H)‐acridinedione as a new class of laser dyes is reported. These dyes lase around 475–495 nm and are compared to the standard dye coumarin 102.
Synthesis of 1‐(4‐substituted)benzyl‐6‐hydroxyisoquinolines with potential activity on NA+,K+‐atpase
Authors: Cerri Alberto , Mauri Paola , Mauro Marina , Melloni Piero 
Published: March 2009

AbstractThe synthesis of 1‐(4‐substituted)benzyl‐6‐hydroxyisoquinolines, to be evaluated in the displacement of the specific 3H‐ouabain binding to Na+,K+‐ATPase, is described. The key step involved a cyclization to the isoquinoline ring under Pictet‐Gams conditions which was best performed with the 6‐hydroxy group protected as the benzyl ether. When an unsaturated ester group was present in position 4 of the 1‐benzyl group, this was best introduced before the cyclization step, since the IIeck reaction on 1‐(4‐bromobenzyl)‐6‐hydroxyisoquinoline (8) with acrylic acid derivatives was not successful in all cases.