bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dihydropyrimidines and related structures. I. N2‐substituted 2‐pyrimidinamines and dihydro‐2‐pyrimidinamines by reaction of phenylbutenones and monosubstituted guanidines
Authors: Wendelin Winfried , Schermanz Karl 
Published: April 2009

AbstractThe reactions of monosubstituted guanidines 2 with phenylbutenones 7 and 10 exclusively yield N2‐substituted 2‐pyrimidinamines 8 and 9. The structure of the reaction products is proved and their differing stability is discussed. Action of methyl‐ and benzylguanidine respectively (2b, c) on 4‐phenyl‐3‐buten‐2‐one (7) and of 2c on l‐phenyl‐2‐buten‐1‐one (10) under atmospheric oxygen affords aromatic N2‐substituted 2‐pyrimidinamines 9b and c. The dihydropyrimidines 8b and c, probable intermediates of the reactions, could not be isolated. In contrast, heating of arylguanidines 2d, e with 7 leads to stable dihydropyrimidinarnines 8d and e, which can be isolated as bases. Addition of methanol to 8d yields 6‐methoxy‐2‐pyrimidinamine 11d, boiling of 8d in DMF affords 9d. Under nitrogen, guanidine adds to 7 to yield aminopyrimidinol 13a, which is transformed by heating in benzene into pyrimidine 9a. The low stability of 8a‐c is attributed to their strong basicity, the greater stability of 8d and e to their lower basicity. The structural formulae of 8d, e and 9b‐d and their salts respectively were established partly (8e) by nmr and partly (9b‐d) by comparison of the corresponding picrates with authentic samples [17].
The reactivity of 4‐hydroxy‐6‐methyl‐2‐pyrone towards aliphatic saturated and α,β‐unsaturated aldehydes
Authors: de March P. , Moreno‐Mañas M. , Casado J. , Pleixats R. , Roca J. L. , Trius A. 
Published: April 2009

Abstract4‐Hydroxy‐6‐methyl‐2‐pyrone (triacetic acid lactone) reacts at C‐3 with 2‐butenal and similar aldehydes by Michael addition. The nonisolated intermediates can undergo transformations in at least five different ways. On the contrary, reaction of the title pyrone with cinnamaldehyde occurs at the carbonyl group of the aldehyde.
The oxidation of 1‐alkyl(aryl)quinolinium chlorides with rabbit liver aldehyde oxidase
Authors: Angelino S. A. G. F. , Van Valkengoed B. H. , Buurman D. J. , Van Der Plas H. C. , Müller F. 
Published: April 2009

Abstract1‐Alkyl(aryl)quinolinium chlorides are oxidized by rabbit liver aldehyde oxidase at positions C‐2 and C‐4. The site and the maximum rate of oxidation are dependent on the size and the steric conformation of the N‐1 substituent. The presence of a 3‐carboxamido group directs the oxidation completely to position C‐4, irrespective of the size of the N‐substituent. Application of covalent amination in liquid ammonia as an “enzyme model” for the oxidation of these compounds shows little resemblance.
A versatile approach to analogues of the cannabinoid‐like anti‐emetic nonabine (BRL 4664)
Authors: Gardner Derek V. , Miller David 
Published: April 2009

AbstractAnalogues of the cannabinoid‐like anti‐emetic nonabine (BRL 4664), in which the 4‐pyridinyl and 1,2‐dimethylheptyl groups have been replaced by other aryl and alky groups respectively, have been synthesised from the appropriate resorcinol by a novel procedure. The route has been shown to be of general applicability, although in the case of nonabine itself the procedure does not represent a viable alternative to that previously published.
Synthesis and antibacterial activity of 2‐phenyl‐4H‐benzo[b]thiopyran‐4‐ones (Thioflavones) and related compounds
Authors: Nakazumi Hiroyuki , Ueyama Tamio , Kitao And Teijiro 
Published: April 2009

AbstractA number of 2‐phenyl‐4H‐benzo[b]thiopyran‐4‐ones (thioflavones) and related compounds have been prepared to test their antibacterial activity. The flavone derivatives were also prepared to compare with their antibacterial activity. It was found that hydroxythioflavones were easily prepared by demethylation of methoxythioflavones with aluminium chloride. In the test of antimicrobial activity, methoxy‐ or hydroxythioflavones were found to be inactive. It is suggested that the sulfone or sulfoxide of thioflavone is required for antimicrobial activities against yeast funguses and molds. These thioflavone derivatives exhibit low acute toxicity.
Voies d'accès aux bisaminopyrimidines pontées par une chaine polyméthylenique
Authors: Menichi Gabriel , Hubert‐Habart Michel 
Published: April 2009

AbstractSeules parmi les produits isomères possibles les N(2),N'(2′) α,ω alcanediylbis(amino‐2 pyrimidines) sont formées lorsque des polyméthylènebisguanidines sont condensées avec l'éthoxyméthylènemalonate d'éthyle, la méthyl‐3 chromone, la flavone, l'acétylacétaldéhyde diméthylacétal, et l'acétyl‐3 éthyl‐2 benzofuranne.
13C NMR spectra and carbon‐proton coupling constants of various methylangelicins
Authors: Rodighiero P. , Manzini P. , Pastorini G. , Guiotto A. 
Published: April 2009

AbstractThe 13C‐nmr spectra of various methyl derivatives of angelicin are reported. The assignment of chemical shifts for all the C atoms has been achieved by using carbon‐proton coupling constants, nuclear Overhauser effect consideration and shift effects caused by the introduction of methyl groups on various positions of the angelicin nucleus. Substituent effects on 13C chemical shifts and carbon‐proton coupling constants are discussed.
A convenient and efficient conversion of diethyl [[[2‐(3‐ or 4‐pyridinyl)‐4‐pyrimidinyl]amino]methylene]propanedioates to higher homologs by base‐catalysed transesterification
Authors: Singh Baldev 
Published: April 2009

AbstractBase‐catalysed transesterification of diethyl [[[2‐(3‐ or 4‐pyridinyl)‐4‐pyrimidinyl]amino]methylene]propanedioates gave higher homolog esters in high yields.
Stereospecific synthesis of new 5‐substituted 6‐methyl‐4,5‐dihydro‐2H‐pyridazin‐3‐ones. X‐ray assignment study
Authors: Taoufik J. , Couquelet J. D. , Couquelet J. M. , Carpy A. 
Published: April 2009

AbstractReaction of hydrazine hydrate with 4,5‐dihydro‐3H‐4‐acetyl furan‐2‐ones I led to ring opening and rearrangement into 6‐methyl‐4,5‐dihydro‐2H‐pyridazin‐3‐ones II (1–20), the structure of which was determined by spectroscopic methods (ir, 1H and 13C nmr). An X‐ray crystal structure study of compound 2 supports the assignment of configuration erythro (5RS, 7SR) for pyridazinones II. Stereochemical courses of this new synthetic route are discussed.
2,1‐benzisothiazoles. XIII. Intermediates and products in the sulfur extrusion reaction of 2,1‐benzisothiazolin‐3(1H)‐one. A new synthesis of 11H‐pyrido[2,1‐b]quinazolin‐11‐one (“pyracridone”)
Authors: Davis Michael , Hook Robert J. , Wu Wen Yang 
Published: April 2009

AbstractTriethyl phosphite abstracts sulfur from 2,1‐benzisothiazolin‐3(1H)‐one (1); a reaction intermediate is the spirocyclic compound 11, and products include the benzoxazine 6 and polyanthraniloyl compounds. In the presence of pyridine, pyracridone (13) is formed. The ketene‐imine 9 is probably not an intermediate in these reactions. The reactions of other nucleophiles with 1 and with its N‐methyl derivative 15, have been examined.
Synthesis of isomeric β‐haloethylthienopyrroles
Authors: Gálvez C. , García F. 
Published: April 2009

AbstractThe preparation of ethyl 4‐(2‐bromoethyl)thieno[2,3‐b]pyrrole‐5‐carboxylate and ethyl 6‐(2‐bromoethyl)thieno[3,2‐b]pyrrole‐5‐carboxylate by reaction of t‐butyl 2‐(2‐thienyl)carbazate and t‐butyl 2‐(3‐thienyl)carbazate with ethyl‐5‐bromo‐2‐oxopentanoate are described.
Reactivity of 1H‐pyrrolo[2,3‐b]pyridine. II. Synthesis of 3‐(β‐haloethyl)‐7‐azaindole
Authors: Gálvez C. , Viladoms P. 
Published: April 2009

AbstractThe preparation of 3‐(2‐chloroethyl)‐7‐azaindole and 3‐(2‐bromoethyl)‐7‐azaindole are described.
Reissert compound studies. XLV. The phenanthridine reissert compound
Authors: Kant Joydeep , Popp Frank D. 
Published: April 2009

AbstractA series of phenanthridine Reissert compounds and Reissert analogs have been prepared using the trimethylsilyl cyanide method. The reactions of the conjugate base and fluoroborate salt have been studied and found, generally, to be similar to those of the isoquinoline Reissert compounds.
Fused‐s‐triazino heterocycles. XI. Displacement reactions of 7,9‐dichloro‐2,5‐bis(trichloromethyl)‐1,3,4,6,9b‐pentaazaphenalene
Authors: Shaw John T. , Rapple Rodney S. , Hicks John C. , Vossers John T. 
Published: April 2009

AbstractThe preparation of 7,9‐dichloro‐2,5‐bis(trichloromethyl)‐1,3,4,6,9b‐pentaazaphenalene (1e) by the chlorination of 2‐trichloromethyl‐5‐methyl‐1,3,4,6,9b‐pentaazaphenalene (1a) using molecular chlorine is described. Displacement of one or both trichloromethyl groups of 1e by a variety of nucleophiles led to the corresponding 7,9‐dichloro‐2,5‐bis‐substituted or 7,9‐dichloro mixed 2,5‐disubstituted derivatives. The reaction of 1a with N‐chlorosuccinimide proved not to be a useful route to 1e but instead led primarily to substitution of positions 7 and/or 9 by chlorine.
Hétérocycles dioxinniques. Nouvelle méthode de synthèse des benzo (4H) dioxinnes‐1,3
Authors: Denis Alain , Delmas Michel , Gaset Antoine 
Published: April 2009

AbstractLa condensation de phénols diversement substitués avec le paraformaldéhyde est étudiée. l'utilisation d'échangeurs d'ions comme catalyseurs associée à un contrôle précis de l'hydratation du milieu réactionnel permet l'obtention hautement sélective des benzo (4H) dioxinnes‐1,3 correspondants.
Reaction of schiff bases with acryl esters. Synthesis of 2‐oxo‐ and 4‐oxotetrahydropyridines
Authors: Barluenga José , Muñiz Laudina , López Fernando , Palacios Francisco , Gotor Vicente 
Published: April 2009

AbstractKetimines react with acryl esters in the presence of aluminium chloride to afford 2‐oxo‐ and 4‐oxotetrahydropyridines. The heterocycles obtained are isolated depending on the structure of the ester and the polarity of the solvent.
Mass spectrometric synthesis. II. The reaction of catechol with acetone in a protic medium
Authors: Podda Gianni , Maccioni Antonio , Daolio Sergio , Traldi Pietro 
Published: April 2009

AbstractThe reaction of catechol with acetone, carried out in the chemical ionization chamber of a VG ZAB 2F mass spectrometer and in the presence of a protic medium (CH5+), leads to 2,2‐dimethyl‐1,3‐benzodioxole. This has been proved by exact measurements and collisionally activated dissociation mass analyzed ion kinetic energy spectra.
Pyrrolo‐ and pyrido[1,2‐a]indoles via an intramolecular wittig reaction
Authors: Crenshaw Michael D. , Zimmer Hans 
Published: April 2009

AbstractSeveral pyrrolo‐ and pyrido[1,2‐a]indoles were prepared via an intramolecular Wittig reaction in good yields. This reaction sequence represents a facile entry into the mitosene ring system.
Substituted 5‐(D,L‐erythro‐1′,2′‐dihydroxypropyl)pyrazines. Potential precursors for the synthesis of biopterin derivatives
Authors: Pastor Stephen D. , Nelson Aaron L. 
Published: April 2009

AbstractA convenient synthesis of substituted 5‐(D,L)‐erythro‐1′,2′‐dihydroxypropyl)pyrazines from crotonic acid 4 is described. The anomalous behavior during decarboxylation of functionalized 2‐oximino‐3‐oxoesters 8a,b is noted. The structures of prepared compounds were determined by spectroscopic methods.
Indole esters as heterocyclic synthons. III. Preparation and reactions of furo[3,2‐b]indoles
Authors: Unangst Paul C. , Carethers Mary E. 
Published: April 2009

AbstractThe preparation of furo[3,2‐b]indoles via Dieckmann cyclization is described. The precursor diesters were obtained from 3‐hydroxy‐1H‐indole‐2‐carboxylic acid esters and methyl or ethyl bromoacetate. Reactions of the furo[3,2‐b]indole enolic esters prepared are discussed.
Determination of rotational barriers of carboncarbon bonds in 2‐arylpiperidines
Authors: Giralt Ernest , Feliz Miguel , Rubiralta Mario , Bosch Joan 
Published: April 2009

AbstractCarbon‐carbon sp3‐sp2rotational barriers of 3,3‐dimethyl‐2‐(3,4,5‐trimethoxyphenyl)‐4‐piperidones and their ethylene ketals have been evaluated using nmr techniques. The conformation of1hydrochloride has been studied by NOE determinations. Values found for the hydrochlorides of the title compounds are discussed in terms of equilibria with free bases and nitrogen inversion.
The synthesis of benzofuroquinolines. III. Two dihydroxybenzofuroquinolinones
Authors: Yamaguchi Seiji , Yoshimoto Yoshiteru , Murai Rikuko , Masuda Fumihiko , Yamada Minora , Kawase Yoshiyuki 
Published: April 2009

AbstractTwo dihydroxybenzofuroquinolinones, 3,9‐dihydroxy‐5H‐benzofuro[3,2‐c]quinolin‐6‐one (V) and 3,8‐dihydroxy‐6H‐benzofuro[2,3‐b]quinolin‐11‐one (VI), were obtained by the demethyl‐cyclization of 3‐(2,4‐dimethoxyphenyl)‐4‐hydroxy‐7‐methoxy‐1H‐quinolin‐2‐one (IV). By the methylation with diazomethane, V gave a dimethylated compound (VII), while VI gave a trimethylated compound (VIII).
On the oxidation of N‐methyl and N‐benzylpyrimidin‐2‐ and ‐4‐ones by rabbit liver aldehyde oxidase
Authors: Angelino S. A. G. F. , Buurman D. J. , van der Plas H. C. , Müller F. 
Published: April 2009

AbstractThe presence of a methyl or benzyl group at N‐1 or N‐3 of 2‐ and 4‐pyrimidone does not affect the site of oxidation by rabbit liver aldehyde oxidase. From all substrates studies only one product viz. the corresponding N‐1 or N‐3 substituted uracil has been obtained. The maximum rates of oxidation by free enzyme show an optimum in the pH range 6.5–7.8, which is little influenced by the site and the size of the N‐substituent. Application of immobilized enzyme in small scale synthesis gives 1‐ or 3‐R‐uracils (R = methyl, benzyl) in 43–78% yield.
Ambident reactivity of a thiazolo[3,2‐a]pyridinium salt with nucleophiles
Authors: Hajós Gy , Messmer A. 
Published: April 2009

AbstractReaction of thiazolo[3,2‐a]pyridinium salt 1 with secondary amines, depending on the reaction condition, may result in both stable pseudo bases 2 as addition products and thiazolyl‐dieneamines 4 as products of ring opening. The ambident reactivity of the title system is interpreted by frontier orbital theory.
Correlation of resonances of strongly coupled spin systems via responses due to strong coupling in homonuclear two‐dimensional j‐resolved spectra: Total assignment of the 1H‐NMR spectrum of 2‐(2′‐pyridyl)‐1,8‐naphthyridine
Authors: Ezell Edward L. , Thummel Randolph P. , Martin Gary E. 
Published: April 2009

AbstractHomonuclear two‐dimensional J‐resolved (2DJ) spectra of molecules containing strongly coupled spin systems contain additional responses and thus additional information, the responses arising from the mixing effects of the 180° pulse employed to create the spin echo upon which the experiment is based. Although additional responses due to strong coupling are generally considered to be an undesirable complication inherent to the experiment, it is shown that they can serve a useful correlation function. Total assignment of the 1H‐nmr spectrum of 2‐(2′‐pyridyl)‐1,8‐naphthyridine at 100 MHz is reported, and members of the three strongly coupled spin systems of the molecule are identified via the additional responses due to strong coupling.
Quinone chemistry. Synthesis and tautomerism of 4,7‐indazolequinones
Authors: Agarwal Nand L. , Bohnstengel Hans , Schäfer Wolfram 
Published: April 2009

AbstractThe reaction of 1 with hydrazines provided hydrazinium‐4,7‐dioxo‐4,7‐dihydroindazol‐3‐olates 2a‐e and 4,7‐indazolequinones 3f,g depending upon the nature of the substituent present in the reactants. Compounds 3a‐g were obtained by treatment of 2a‐e with sodium hydroxide. Fixed tautomers 4a‐b and 5c‐f were synthesized by methylation of the corresponding 3a‐f or 2a‐2e with diazomethane. Migration of a methyl group of 5c‐f from the oxygen at C3 to N1 on heating afforded 6c‐f. The tautomerism of 2a‐e and 3a‐g has been studied by comparing ir, uv, 1H nmr and 13C nmr spectra with those of the fixed tautomers.
Studies on quinones. XIII. Synthesis and reactivity in acid medium of cyclic O,N‐ketals derived from acylbenzoquinones and enamines
Authors: Cassis RaÚL , Tapia Ricardo , Valderrama Jaime A. 
Published: April 2009

AbstractA series of cyclic O,N‐ketals 14–20 derived from benzo[b]furan has been synthesized by reaction of acylbenzoquinones and enamines. Compounds 14–20, in warm aqueous sulfuric acid, react to give elimination or rearrangement products depending on the structure of the substrate. The behavior of heterocycles 14–20 in acid conditions is interpreted on the basis of the arrangement of the carbon substituents on the furan ring.
Synthesis and reduction of 5,5‐dimethyl‐2,4‐bis(3,4‐dimethoxyphenyl)‐2‐chloro‐2,5‐dihydrofuran
Authors: Biftu Tesfaye 
Published: April 2009

AbstractA new, stable 5‐membered ring heterocyclic cation was prepared and reduced into the corresponding dihydrofuran, tetrahydrofuran and pentanol derivatives.
Studies on phenothiazines. Part 11. Synthesis and spectral studies of substituted 1‐chloro/methyl/nitrophenothiazines
Authors: Gupta R. R. , Kalwania G. S. , Kumar M. 
Published: April 2009

AbstractSynthesis of the title compounds by the Smiles rearrangement has been reported. 1‐Nitrophenothiazines have been prepared by the reaction of 2‐amino‐3‐chloro/methyl/methoxythiophenol with substituted o‐halonitrobenzenes in ethanolic sodium hydroxide, in which Smiles rearrangement occurs in situ. 1‐chloro/methyl‐7‐substituted phenothiazines have been prepared by Smiles rearrangement of 3‐chloro/methyl‐2‐formamido‐2′‐nitro‐4′‐substituted diphenyl sulphides. The latter were prepared by the formylation of the diphenyl sulphides obtained by the condensation of 2‐amino‐3‐chloro/methylthiophenols with substituted o‐halogenonitrobenzenes in ethanolic sodium acetate. Spectral studies are also included.
The behavior of 6‐p‐chlorostyryl‐3‐thioxo‐1,2,4‐triazin‐5‐one toward phenylmagnesium bromide
Authors: Zaher H. A. , Mohammady R. , Ibrahim Yehia A. 
Published: April 2009

AbstractThe action of phenylmagnesium bromide on 6‐p‐chlorostyryl‐3‐thioxo‐1,2,4‐triazin‐5‐one (1) was studied whereby a mixture of seven products was obtained. These were separated and characterised, and a reasonable mechanism for their formation is presented and discussed.
The regioselective alkylation of 4,6‐dimethyl‐1‐phenyl‐2(1H)‐pyrimidinone
Authors: Katoh Akira , Omote Yoshimori , Kashima Choji 
Published: April 2009

Abstract4,6‐Dimethyl‐1‐phenyl‐2(1H)‐pyrimidinone (I) was treated with alkyl halides in the presence of sodium hydride at low temperature to afford only C‐6 alkylated products III and IV in good yields. Further, the mono‐, IIIa‐d, and di‐alkylated 2(1H)‐pyrimidinones IVa‐d were selectively obtained by changing the amount of alkyl halides.
Synthesis and mass spectrum of 3,3′‐thiobispyridine and polarographic reduction of 1,1′‐dimethyl‐3,3′‐thiobispyridinediium diiodide
Authors: Summers Lindsay A. , Trotman Sylvia 
Published: April 2009

Abstract3,3′‐Thiobispyridine is prepared by reaction of pyridine‐3‐thiol with 3‐bromopyridine. The base peak in the mass spectrum of 3,3′‐thiobispyridine is due to the molecular ion which fragments by loss of H, HCN and CS as well as by central bond rupture. The 1,1′‐dimethyl diquaternary salt of 3,3′‐thiobispyridine is reduced polarographically by a one electron transfer not involving hydrogen to an unstable radical cation at a potential (Eo) of −0.72 V in the pH range 7.4–11.2.
Two‐dimensional relayed coherence transfer experiments as a means of subgrouping protonated carbon resonances of complex polynuclear heteroaromatics on the basis of vicinal proton‐proton connectivities
Authors: Musmar M. J. , Martin Gary E. , Tedjamulia Marvin L. , Kudo Hirotaka , Castle Raymond N. , Lee Milton L. 
Published: April 2009

AbstractApplication of autocorrelated homonuclear (COSY) and proton‐carbon chemical shift correlation two‐dimensional nmr experiments to the problem of assigning the 1H‐ and 13C‐nmr spectra of phenanthro[4,3‐a]dibenzothiophene fails despite their considerable utility in the assignment of the spectra of the smaller phenanthro[b]thiophenes. The failure of these techniques in the case of phenanthro[4,3‐a]dibenzothiophene is predominantly due to the inability of the COSY spectrum to provide the means of subgrouping the proton resonances into their component spin subsystems. Two‐dimensional relayed coherence transfer nmr experiments which first established coherence between vicinally coupled protons which is then transferred to the carbon spins which are ultimately observed circumvent these problems. The application of two‐dimensional relayed coherence transfer to phenanthro[4,3‐a]dibenzothiophene is described, the technique leading to the sub‐grouping of all five of the proton spin subsystems and thus providing a means of beginning the total assignment.
Synthesis and reactivity of 1‐methyl‐3‐phenyl‐4‐diazo‐5‐benzoylamidopyrazole. A potential antitumor agent
Authors: Cecchi Lucia , De Sio Francesco , Melani Fabrizio 
Published: April 2009

AbstractThe title compound 2 was prepared in excellent yield by diazotation of the parent amino derivative. Compound 2 was found to react with a variety of acyclic and cyclic active methylene compounds to yield the corresponding pyrazolo‐4‐ylhydrazones.
The synthesis of isoindolin‐3‐ones, Phthalazin‐4(3H)‐ones and related systems
Authors: Dunn A. D. 
Published: April 2009

AbstractThe reaction between methyl 2‐cyanobenzoate and its pyridine analogues gave isoindolin‐3‐ones, phthalazin‐4(3H)‐ones and their corresponding aza analogues. Some reactions of 1‐benzylaminoiminoisoindolin‐3‐one 5b were investigated.
The synthesis of pyrrolopyridines and pyridopyridazines
Authors: Dunn A. D. 
Published: April 2009

AbstractThe synthesis of the aza analogues 3a‐d of 1‐iminoisoindolin‐3‐one 1 and their use in the preparation of pyrrolopyridines and pyridopyridazines is described. The synthesis of derivatives of these imines is also reported.
Sulfur derivatives of 1‐methylpyrrole
Authors: Gronowitz Salo , Kada Rudolf 
Published: April 2009

AbstractMetalation of 1‐methylpyrrole using n‐butyllithium and tetramethylethylenediamine (TMEDA) in ether furnished 1‐methyl‐2‐pyrrolyllithium, which in turn was converted to 1‐methyl‐2‐methylthiopyrrole upon treatment with dimethyldisulfide. Further formylation with dimethylformamide, phosphorus oxychloride in dichloroethane led to the corresponding pyrrole‐2‐carboxaldehyde, which was then condensed with malononitrile and methylcyanoacetate under Knoevenagel reaction conditions to give 2‐cyano‐3‐(1‐methyl‐5‐methylthio‐2‐pyrrolyl)acrylonitrile and 2‐cyano‐3‐(1‐methyl‐5‐methylthio‐2‐pyrrolyl)acrylic acid methyl ester, respectively. Their oxidation by hydrogen peroxide furnished the corresponding sulfones. Analogously, 5‐phenylthio derivatives were prepared.
Studies on 8‐aminoquinoline 1‐oxide antimalarial agents
Authors: Johnson Judith L. , Worth Donald F. , Colbry Normal L. , Werbel Leslie M. 
Published: April 2009

AbstractThe synthesis of N‐oxides of 8‐aminoquinolines related to primaquine has been explored in an effort to obtain a less toxic, curative, antimalarial drug. Several side chain N‐oxide analogs (2b, 3b) were prepared as well as the ring N‐oxide of primaquine with both amines trifluoroacetylated (13). All attempts to deblock this material failed. Trifluoroacetylation of primaquine also yielded the novel acyl analog 12 which had curative activity versus P. cynomolgi in the monkey about equal to that of primaquine.