bluuebunny/crossref_metadata_2025_split huggingface dataset:
The synthesis of benzo[c]cinnoline 5,6‐dioxides and related compounds
Authors: Kempter Fritz E. , Castle Raymond N. 
Published: March 2009

AbstractThe preparation of a variety of benzo[c]cinnolines as well as benzo[c]cinnoline monoxides and dioxides by reduction of the corresponding 2,2‐dinitrobiphenyls with hydrogen and Raney nickel of low activity is described. The detailed procedures developed produce superior yields of benzo[c]cinnoline monoxides and dioxides. The structure of some intensely‐colored red‐violet amino, alkylamino, and hydroxybenzo[c]cinnoline monoxides and dioxides is discussed and these are compared with the essentially colorless alkoxyl and acetylamino derivatives. The long wave length band in the U. V. spectrum of the colored compounds is compared.
Substitution reactions of 4‐methyldibenzothiophene
Authors: Campaigne E. , Hewitt L. , Ashby John 
Published: March 2009

AbstractSuccinoylation, acetylation and nitration of 4‐methyldibenzothiophene yields 2‐substituted products. Bromination however, gave 3‐bromo‐4‐methyldibenzothiophene as the major product along with a small amount of the 2‐isomer. The bromo‐compounds were used to prepare related derivatives via lithium exchange. 4‐Methyldibenzothiophene 5,5‐dioxide was also shown to nitrate in the 3‐position. The structures of the derivatives were determined by NMR analyses. An alternative synthesis of 4‐methyldibenzothiophene is described.
Syntheses in the pyridazine series. XXX. Protonation and quaternization studies on imidazo[1,2‐b] pyridazines and s‐triazolo[4,3‐b] pyridazines
Authors: Japelj M. , Stanovnik B. , Tišler M. 
Published: March 2009

AbstractSterically unhindered s‐triazolo[4,3‐b] pyridazines form N1‐methiodides, whereas 3‐ and/or 8‐substituted analogs form a mixture of N1‐ and N2‐methiodides. In some cases thermal rearrangement occurred. Imidazo[1,2‐b]pyridazines form N1‐methiodides and here also steric interactions were observed as evidenced by the NMR spectra.
1,2,3‐benzotriazines. IV. The chemical reactivity of benzimidazo[1,2‐c] [1,2,3]benzotriazine
Authors: Spector Richard H. , Joulliéa Madeleine M. 
Published: March 2009

AbstractThe reactions of benzimidazo[1,2‐c][1,2,3]benzotriazine (1) with fluoroboric acid, potassium iodide and phenyl isothiocyanate are described. The structure of the phenyl isothiocyanate product is elucidated by chemical and spectroscopic techniques. The reaction of 1 with alcoholic potassium hydroxide is shown to proceed by a free radical mechanism. The structure of the compound formed from 1 and sodium diethyl malonate is investigated by spectroscopic methods. The reduction and photochemical reactivity of 1 are also discussed.
Dithioheterocycles from ethane‐1,2‐disulfenyl chloride
Authors: Mueller Wolfgang H. , Dines Martin 
Published: March 2009

AbstractA convenient route to 1,4‐dithianes from ethane‐1,2‐disulfenyl chloride and acetylenes is presented. The reaction of this new sulfenyl halide with primary and secondary amines is also discussed.
Heterocyclic N‐glycosides. III. Synthesis of N‐glycosyl‐v‐triazoles from glycosyl azides and phenylacetylene
Authors: Garcíaa‐Lóapez M. T. , Garcíaa‐Mun̈toz G. , Iglesias J. , Madroïtero R. 
Published: March 2009

AbstractA number of v‐triazoles were prepared by the 1,3‐dipolar cycloaddition of glycosyl azides on phenylacetylene. In all the cases studied, except when 2‐O‐trichloroacetyI‐3,4,6‐tri‐O‐acetyl‐α‐D‐glucopyranosyl azide was used, the two possible v‐triazoles were obtained. The assignment of structure and anomeric configuration for all N‐glycosides obtained is discussed.
Base catalyzed isomerization of epoxides. I. The isomerization of β‐chloroepoxides
Authors: Sheng M. N. 
Published: March 2009

AbstractThe base catalyzed isomerizations of epichlorohydrin, 1‐chloro‐2,3‐epoxy‐2‐methylpropane, 1‐chloro‐2,3‐epoxybutane, and 3‐chloro‐1,2‐epoxybutane have been studied, using lithium ortho‐phosphate as the basic catalyst. Chloroketones and dichloro‐alcohols are the major products. This is the first example of a compound with an electron withdrawing group attached to the carbon atom adjacent to the oxirane ring which undergoes the α‐elimination pathway. A bidirectional mechanism is proposed to explain the experimental results. The stereochemistry of the hydrochlorination of 1‐chloro‐2,3‐epoxybutane and 3‐chloro‐1,2‐epoxybutane has also been studied.
A study of some 1‐alkyl‐2,3‐dihydroimidazo[1,2‐a]benzimidazoles
Authors: North Robert J. , Day Allan R. 
Published: March 2009

AbstractA series of 1‐alkyl‐7‐nitro (and 7‐amino)‐2,3‐dihydroimidazo[1,2‐α]benzimidazoles has been prepared. Similarly, a series of 1‐alkyl‐2,3‐dihydroimidazo[1,2‐α]benzimidazoles has been prepared. The prototropic tautomerism of this system has been studied. The site of electrophilic attack (alkylation) has been examined. 1‐Alkylation takes place under strongly basic conditions and 9‐alkylation occurs under neutral conditions.
5,8‐isoquinolinediones. II. Chemical and electrochemical behavior of the 5,8‐isoquinolinedione system
Authors: Joulliéa Madeleine M. , Puthenpurayil Joseph K. 
Published: March 2009

AbstractWe have devised two general synthetic schemes to 5,8‐isoquinolinediones and have investigated the chemical and electrochemical behavior of these compounds. The 1,4‐addition reactions of these quinones with amines was shown to occur at the 7‐position and a number of 7‐amino‐5,8‐isoquinolinediones. were synthesized. The 1,4‐addition of hydrogen bromide was also studied. The ethylenic double bond of the 5,8‐quinone system underwent Diels‐Alder additions to yield the oxidized forms of the adducts. The nucleophilic displacement of the methoxy group in 7‐methoxy‐5,8‐isoquinoline was accomplished with both potassium hydroxide and morpholine. A Polarographic study of the half‐wave potentials of substituted 5,8‐isoquinolinediones showed a linear correlation between the change in the half‐wave potential of the quinone system (ΔE° 1/2) resulting from the introduction of different substituents, and the substituent constants (σp‐x).
Synthesis of 5‐aryl‐2‐oxazolepropionic acids and analogs. Antiinflammatory agents
Authors: Short Franklin W. , Long Loren M. 
Published: March 2009

AbstractCondensation of 2‐bromoacetophenones with sodium succinimide gave N‐phenacylsuccinimides (1) which were opened with sodium hydroxide to N‐phenacylsuccinamic acids (2). The latter were cyclized to 5‐aryl‐2‐oxazolepropionic acids (3) in sulfuric acid. Similar cyclization of N‐phenacylphthalamic acid (5) and succinic acid 2‐benzoylhydrazide (7) gave o‐(5‐phenyl‐2‐oxazolyl)benzoic acid (6) and 5‐phenyl‐1,3,4‐oxadiazole‐2‐propionic acid (8). The succinamic acids 2 and the phthalamic acid 5 were observed to recyclize to the corresponding imides (1 and 4) on heating, and the succinic acid hydrazide 7 was similarly cyclized to N‐benzamidosuccinimide (9) with acetic anhydride. Antiinflammatory screening data are reported for 3, 6 and 8.
Synthesis and structure of 5‐oxo‐1‐phenylpyrazoline‐3‐ and 4‐alkanoic acids. Antiinflammatory agents
Authors: Short Franklin W. , Schoeb Ernest J. 
Published: March 2009

AbstractCondensation of appropriate β‐keto esters with phenylhydrazine gave 5‐oxo‐1‐phenyl‐2‐pyrazoline‐3‐and 4‐alkanoic esters 1 and 3 which were saponified to the corresponding alkanoic acids 2 and 4. Analogous condensation of the same β‐keto esters with hydrazobenzene gave 5‐oxo‐1,2‐diphenyl‐3‐pyrazoline‐3‐and 4‐alkanoic esters 5 and 7 which were similarly converted to acids 6 and 8. The structures of the oxopyrazolines as revealed by their infrared absorption are discussed, and results of their antiinflammatory screening are reported.
The chemistry of a ketene‐sulfur dioxide adduct
Authors: Gomes Ailton De Souza , Joulliéa Madeleine M. 
Published: March 2009

AbstractWe have demonstrated the formation of a reactive species from ketene and sulfur dioxide and have investigated some of its reactions. The 3 + 2 ← 5 cycloaddition reactions of this intermediate with benzylideneaniline and its derivatives gave the corresponding 2,3‐diphenylthiazolidin‐4‐one 1,1‐dioxides. The reduction of 2,3‐diphenylthiazolidin‐4‐one 1,1‐dioxide with lithium aluminum hydride yielded the corresponding thiazolidine. Aniline and its derivatives reacted with the ketene‐sulfur dioxide adduct to give thioaceto‐1,3‐dianilide 3‐oxide. o‐Phenylenediamine gave [2,1,5]benzothiadiazepin‐4‐one 2‐oxide, a derivative of a new ring system, [2,1,5]benzothiadiazepine. o‐Aminophenol yielded [1,2,5]benzothiazepin‐4‐one 2‐oxide.
Application of a thermal rearrangement reaction to questions of structure of condensed dihydrodiazepinones: The reaction of 2,3‐diaminopyridine with ethyl benzoylacetate
Authors: Israel Mervyn , Jones Lynne C. 
Published: March 2009

AbstractThe condensation of an unsymmetrical aromatic diamine with a β‐ketoester can afford two theoretically possible dihydrodiazepinone products, differentiation between which is, at best, difficult and laborious. A recently described (3) rearrangement reaction, whereby dihydrodiazepinones are thermally converted into N‐substituted imidazolones, has now been applied to the elucidation of structures of ambiguous diazepinone derivatives. By means of the thermal rearrangement method, the diazepinone derivative resulting from the reaction of 2,3‐diamino‐pyridine and ethyl benzoylacetate, for which structures 1a and 1b are equally plausible, has been definitively characterized as the 2‐phenyl‐4‐one compound, 1a.
5‐Isoxazolylhydrazines. Reduction of 5‐isoxazolones to isoxazoles
Authors: Adembri G. , Ponticelli F. , Tedeschi P. 
Published: March 2009

Abstract5‐Isoxazolylhydrazines III were obtained from 5‐isoxazolones I, via the 5‐haloisoxazoles II. The decomposition of the tosyl derivatives of III results in unambigous syntheses of 3,4‐disubstituted isoxazoles.
\documentclass{article}\pagestyle{empty}\begin{document}$ \left[\!\left[ {} \right.\right. $ \end{document}[(Dialkylamino)alkyl]amino\documentclass{article}\pagestyle{empty}\begin{document}$ \left.\left. {} \right]\!\right] $ \end{document}pyrimido[1,2‐a]benzimidazoles,2,3‐dihydro‐1H‐cyclopenta[4,5]pyrimido[1,2‐a]benzimidazoles, and s‐triazolo[1,5‐a]pyrimidines as potential antimalarial agents
Authors: Werbel Leslie M. , Curry Ann , Elslager Edward F. , Hess Carolyn A. , Hutt Marland P. , Youngstrom Carl 
Published: March 2009

AbstractThe structure of the product of the reaction of 2‐aminobenzimidazole with ethyl aceto‐acetate has been established by NMR spectroscopy as 2‐melhylpyrimido[1,2‐a]benzimidazol‐4‐ol (III). 7(and 8)‐Chloro‐2‐methylpyrimido[l,2‐a]benzimidazol‐4‐ol (VI and VIII, R  OH), 2‐(trifluoromethyl)pyrimido[i,2‐a]benzimidazol‐4‐ol (X), 2,7,8‐trimethylpyrimido[1,2‐a]benzimidazol‐4‐ol (XII), 2‐benzyl‐1,2,3,4‐tetrahydropyrido[4′,3′:4,5]pyrimido[1,2‐a]benzimidazol‐12‐ol (XIII), 1,2,3,4‐tetrahydrobenzimidazo[2,1‐b]quinazolin‐12‐ol (XIV), and 2,3‐dihydro‐1H‐cyclopenta[4,5]pyrimido[1,2‐a]benzimidazol‐11‐ol (XV) were prepared in a similar manner. Chlorination of III, VI and VIII, XV, and 5‐methyl‐s‐triazolo[1,5‐a]pyrimidin‐7‐ol (XXV, R  OH) with phosphorus oxychloride afforded the corresponding chloroheterocycles, which were condensed with the appropriate N,N‐dialkylalkylenediamine or Nα,Nα‐diethyl‐6‐methoxytoluene‐α,3‐diamine to give various 4‐\documentclass{article}\pagestyle{empty}\begin{document}$ \left[\!\left[ {} \right.\right. $ \end{document}[(dialkylamino)alkyl]amino\documentclass{article}\pagestyle{empty}\begin{document}$ \left[\!\left[ {} \right.\right. $ \end{document}‐2‐methylpyrimido[1,2‐a]benzimidazoles (Va‐e, VII, IX), 11‐\documentclass{article}\pagestyle{empty}\begin{document}$ \left.\left. {} \right]\!\right] $ \end{document}[(dialkylamino)alkyl]amino\documentclass{article}\pagestyle{empty}\begin{document}$ \left[\!\left[ {} \right.\right. $ \end{document}‐2,3‐dihydro‐1H‐cyclopenta[4,5]‐pyrimido[1,2‐a]benzimidazoles (XVIa and b), and 7‐\documentclass{article}\pagestyle{empty}\begin{document}$ \left[\!\left[ {} \right.\right. $ \end{document}[(dialkylamino)alkyl]amino\documentclass{article}\pagestyle{empty}\begin{document}$ \left.\left. {} \right]\!\right] $ \end{document}‐5‐methyl‐s‐triazolo[1,5‐a]pyrimidines (XXVb‐e). None of these compounds displayed significant antimalarial activity against Plasmodium berghei in the mouse.
Electronolysis of some derivatives of selenochromane
Authors: Buu‐Hoi N. P. , Mangane M. , Périn‐Roussel O. , Renson M. , Ruwet A. , Maréchal M. 
Published: March 2009

AbstractThe mass spectra of 4‐selenochromanone, 4‐hydroxyselenocoumarin, and 3,3′‐methylene bis(4‐hydroxyselenocoumarin) have been determined, and the fragmentation pathways of these substances under electron‐impact are discussed. A strong tendency to form the benzoselenophen ring was noted in all three cases.
A kinetic investigation of the addition of diazomethane to styrenes. Role of dipolar aprotic solvents in predicting direction of dipole orientation
Authors: Kadaba Pankaja K. , Colturi Thomas F. 
Published: March 2009

AbstractThe addition of diazomethane to a series of substituted styrenes has been kinetically investigated with emphasis on polar, solvent, and solvation effects. Although the reaction is generally insensitive to solvent polarity, a sizeable substituent effect (ρ = +0.90) has been observed. Also, a sizeable increase in rate was generally observed in protic solvents such as water, and a considerable rate enhancement occurred in the case of nitrostyrene in the dipolar aprotic solvent, dimethylformamide. The results are discussed in terms of a concerted mechanism involving a partially‐charged transition state II, with negative charge formation on the α‐carbon of the styrene.The methoxystyrene offers an exception to the Hammett equation and the unexpectedly high rate constant for this compound could be discussed in terms of a possible participation of the highly nucleophilic resonance form of p‐methoxystyrene and an α‐addition via the transition state III. However, solvation effects in dimethylformamide (failure to obtain the anticipated rate increase) and the formation of a 3‐substituted pyrazoline adduct from the cycloaddition reaction indicate steric control to predominate over electronic factors and β‐addition to prevail unequivocally.It is proposed that solvation effects in protic solvents can be utilized to advantage in cycloaddition reactions leading to 1‐pyrazolines, for which no other routes are available at the present time.
Molecular spectra and molecular structure of heterocyclic compounds. Infrared and near ultraviolet absorption spectra of pyridine N‐oxide derivatives
Authors: Ghersetti S. , Maccagnani G. , Mangini A. , Montanari F. 
Published: March 2009

AbstractThe infrared and ultraviolet spectra of many pyridine N‐oxide derivatives have been studied.Ultraviolet spectra show a strong solvent effect in going from aprotic to hydroxylic solvents due to strong hydrogen bonding. Values of δ H° for several systems CH3OH/XPyNO in tetra‐chloroethylene solution were evaluated by infrared techniques and a linear correlation δ H° vs. δ v OH has been found.Features of the infrared and ultraviolet characteristic absorption bands were also investigated.
Some methyl substituted benzo[b]naphtho[2,3‐d]thiophenes
Authors: Campaigne E. , Ashby John , Osborn S. W. 
Published: March 2009

AbstractSeven benzo[b]naphtho[2,3‐d]thiophenes have been prepared with methyl groups substituted in the 6,7, and 8‐positions. These compounds are structurally related to the sulfur analogs of cholanthrene and methylcholanthrene.
The chemistry of phosphole derivatives
Authors: Hughes A. N. , Srivanavit Chit 
Published: March 2009

AbstractSynthetic approaches to, and the chemistry of, phospholes, benzophospholes and dibenzophospholes are reviewed and particular attention is paid to the possible aromatic character of the phosphole ring. Systems containing the 2H‐ and 3H‐phosph(V)ole nucleus are surveyed as are phosphole derivatives containing pentacovalent and six‐coordinate phosphorus. Stereochemical considerations in the more complex phosphole derivatives are discussed.
The azomethine nitrene. I. Pyrolysis and photolysis of Δ2 1,2,4‐oxadiazoline‐5‐ones
Authors: Boyer J. H. , Frints P. J. A. 
Published: March 2009

AbstractBoth photolytic and pyrolytic fragmentation of the oxadiazolone ring produces carbon dioxide and a residue which may exist in part as an intermediate azomethine nitrene and may react with or without rearrangement and/or further fragmentation. Rearrangement produces carbodiimides 2 and cyanamides 6. Thermal and photo‐isornerization of carbodiimides into cyanamides provides a key step in an explanation for the formation of the latter from an oxadiazolone. A highly selective cyclization produces a benzimidazole 3 when a suitable aryl subsliluent is at nitrogen. The formation of N‐phenylbenzamidine 7a from 3‐phenyl‐4‐benzyloxadiazolone 5c requires a 1,4‐migration from carbon to nitrogen followed by hydrolysis. The same or similar migration of hydrogen and subsequent ring‐closure with dehydrogenation provides the formation of 2‐phenyl‐quinazoline 8. Products which require no rearrangement of the residue include amidines 7 and triazoles 10. A portion of each triazole corresponds to a nitrile, in turn a product along with a simple nitrene;, of more extensive fragmentation of the; oxadiazolone ring. Phenyl, benzyl, and cyclohexyl nitrenes are respectively detected by the isolation of aniline, benzaldehyde and cyclohexanone. Other recombination reactions bring about the formation of triphenyltriazine 13 and triphenylimidazole 14.
Azonia polycyclic quinones, o‐diazo‐oxides and related products
Authors: Fields D. L. , Miller J. B. 
Published: March 2009

Abstract4α‐Azoniaanthracene‐5,6‐ and 5,8‐dione salts have been prepared by nitric acid oxidation of their respective diols, and are shown to function as either an electrophilic dienophile or a diene component in Diels‐Alder‐type reactions. Several azonia o‐quinones have been treated with tosylhydrazine in methanol saturated with hydrogen chloride to give unusually stable o‐diazo‐oxides. A four‐step dehydroxylation procedure is detailed for the conversion of .5,6‐dihydroxy‐4α‐azonia‐anthracene salts to new 5‐hydroxy‐4α‐azoniaanthracene salts.
Synthetic studies on mesoionic compounds. The mesoionic 1,3‐diazol‐4‐one system
Authors: Roche E. B. , Stansloski D. W. 
Published: March 2009

AbstractThe synthesis of the mesoionic 1,3‐diazol‐4‐one system is discussed. The intermediate to this system and the attempted cyclizations are described in detail. Further comments on the stability of these mesoionic compounds are also made.
Enzymic phenol oxidation of N‐methylcoclaurine. Studies on the syntheses of heterocyclic compounds. Part cccxxxii
Authors: Kametani Tetsuji , Nemoto Hideo , Kobari T. , Takano Seüchi 
Published: March 2009

AbstractThe enzymic phenol oxidation of N‐methylcoclaurine (111) with homogenized potato peels in the presence of hydrogen peroxide was examined and found to give a mixture of the dimer (VI) and trimer (VII) with C‐O‐C head to tail coupling. Furthermore, the same oxidation of III with homogenized rhizome of Nelumbo nucifera Gartner and hydrogen peroxide was also investigated.
The rearrangement of glycicyl N‐phenylcarbamate
Authors: Farrissey W. J. , Nashu A. Munim 
Published: March 2009

AbstractThe thermal rearrangement of glycicyl N‐phenylcarbamate yields 3‐phenyl‐4‐hydroxymethyl‐2‐oxazolidone and not 3‐phenyl‐5‐hydroxytetrahydro‐1,3‐oxazin‐2‐one as reported previously.
Spectrophotometric determination of the second dissociation constants of the aminoquinolines
Authors: Brown Ellis V. , Plasz Andrew C. 
Published: March 2009

AbstractThe second dissociation constants representing the transition from monocation to dication for all of the isomeric aminoquinolines have been determined as pKa' values. The analogous values for 2‐ and 4‐aminopyridine have been recalculated using a revised HO scale. The accurate determination of the second pKa values follows from measurement, for the first time, of the ultraviolet spectra of all the mono‐ and dications of the aminoquinolines.
Picrylamino‐substituted heterocycles. IV. Pyrazoles
Authors: Coburn Michael D. 
Published: March 2009

AbstractThis paper describes the synthesis of various picryl‐ and picrylamino‐substituted pyrazoles. These compounds were prepared by condensing the appropriate pyrazole or aminopyrazole with a picryl halide or picrylpyrazole. Some of these materials could be nitrated under carefully controlled conditions to the corresponding nitropyrazole derivatives. The products were identified by n.m.r. spectroscopy, and their crystal densities and thermal stabilities were determined. Drop‐weight impact sensitivities were measured for some of the more interesting compounds.
Ferrocene studies. IV. Some furan containing derivatives of ferrocene
Authors: Popp Frank D. , Moynahan E. Bradley 
Published: March 2009

AbstractThe condensation of ferrocenecarboxyhydrazide, ferrocenecarboxaldehyde and acetylferrocene with a number of furan derivatives is reported. The reaction of chalcones containing both the furan and the ferrocene nucleus with Phenylhydrazine and hydrazine proceeds to yield pyrazolines.
A study of some octahydroimidazo[1,5‐a] pyridines. A new example of ring‐chain tautomerism
Authors: Beim Howard J. , Day Allan R. 
Published: March 2009

AbstractA series of 3‐substituted octahydroimidazo[1,5‐a]pyridines has been prepared. An nmr study at several temperatures showed that 3‐phenyloctahydroimidazo[1,5‐a] pyridine (XIII) and 3‐t‐butyloctahydroimidazo[1,5‐a] pyridine (XIV) exhibited ring‐chain tautomerism. The n‐propyl (X), isopropyl (XI) and benzyl (XII) derivatives did not show this form of isomerism. It has also been shown that Crabb and Newton's statement (3) that Freed and Day (1) had failed to obtain the parent compound, octahydroimidazo[1,5‐a]pyridine (1), is incorrect.
2‐Phenyl‐5‐(trichloromethyl)‐1,3,4‐oxadiazoles, A new class of antimalarial substances
Authors: Hutt Marland P. , Elslager Edward F. , Werbel Leslie M. 
Published: March 2009

AbstractAn investigation of hybrids of 2,5‐dimethyl‐1,3,4‐oxadiazole (I) and α,α,α,α',α',α'‐hexachloro‐p‐xylene (Hetol®) (II) as potential antimalarial agents led to the synthesis of representative 2‐phenyI‐5‐(trichloromethyl)‐1,3,4‐oxadiazoles (VIa‐f, VIII‐X) and related trichloromethyl 1,2,4‐oxadiazole, 1,3,4‐oxadiazoles, and 1,3,4‐thiadiazole (VII, XIII‐XV). Treatment of the appropriately substituted benzoic: acid hydrazides (IVa‐f) with trichloroacetic anhydride afforded the intermediate 1‐benzoyl‐2‐(triehloroacetyl)hydrazines (Va‐f) which were cyclized to the desired 5‐(chlorophenyl, tolyl, or α,α,α‐trifluorotolyl)‐2‐(trichloromethyl)‐1,3,4‐oxadiazoles (VIa‐f) (44–66%) in situ utilizing phosphorous oxychloride. Chlorination of the 5‐tolyl‐2‐(trichloromethyl)‐1,3,4‐oxadiazoles (VId‐f) afforded 2‐(trichloromethyl)‐5‐(α,α,α‐trichloro‐m‐ and p‐tolyl)‐1,3,4‐oxadiazole (VIII and IX) and 2‐(α,α,α,α',α',α'‐hexachloro‐3,5‐xylyl)‐5‐(trichloromethyl)‐1,3,4‐oxadiazole (X) in 23–56% yield. Each of the 2‐phenyl‐5‐(trichloromethyl)‐1,3,4‐oxadiazoles (VIa‐f, VIII‐X) was active against Plasmodium berghei in mice when administered in single 160 or 640 mg./kg. subcutaneous doses or given orally by drug‐diet for 6 days at doses of 29–336 mg./kg./day. The 2‐(trichloromethyl)‐5‐(α,α,α‐trichlorotolyl)‐1,3,4‐oxadiazoles (VIII‐X) were the most active compounds prepared and exhibited activity against P. berghei comparable with Hetol®. Structure‐activity relationships are discussed.
3H‐Indol‐3‐ols by a novel ring contraction
Authors: Lednicer Daniel , Emmert D. Edward 
Published: March 2009

AbstractTreatment of α‐hydroxy‐α‐phenyl‐o‐toluidide with phosphorus tribromide afforded a series of 4H‐3,1‐benzoxazines. These last, when reacted with potassium amide in liquid ammonia, ring contracted to 2,3‐disubstituted 3H‐indol‐3‐ols. The scope of this rearrangement was examined. The indolols on treatment with hot base were found to rearrange to indoxyls. Several of these as well as their N‐alkylation products are described.