bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of pyrimido[4,5‐e][1,4]oxazepin‐5‐ones
Authors: Santilli Arthur A. , Kim Dong Han , Wanser Stephen V.
Published: March 2009

Eighteen novel pyrimido[4,5‐e][1,4]oxazepin‐5‐ones were prepared directly via the reaction of either ethyl 4‐chloro‐2‐phenyl‐5‐pyrimidinecarboxylate (Ia) or ethyl 4‐chloro‐2‐m‐chlorophenyl‐5‐pyrimidinecarboxylate (Ib) with a variety of substituted 2‐(alkylamino)ethanols. A typical example was the preparation of 8,9‐dihydro‐9‐methyl‐2‐phenylpyrimido[4,5‐e][1,4]‐oxazepin‐5(7H)‐one (IIa) from the reaction of Ia with 2‐(methylamino)ethanol. Hydrolytic cleavage of the lactone ring in IIa with sodium hydroxide solution, followed by acidification with hydrochloric acid afforded 4‐[(2‐hydroxyethyl)methylamino]‐2‐phenyl‐5‐pyrimidinecarboxylic acid (IV). Reactions of IIa with concentrated ammonium hydroxide or hydrazine also caused cleavage of the lactone ring, giving the corresponding amide (V) or hydrazide (VI), respectively. Structural assignments were supported by infrared and nuclear magnetic resonance spectra.
Preparation of some 4‐hydroxyl‐1‐methyl‐1H‐2,1‐benzothiazine‐3‐carboxanilide 2,2‐dioxides
Authors: Lombardino Joseph G.
Published: March 2009

An improved, 3‐step synthesis of 3,4‐dihydro‐1‐methyl‐1H‐2,1‐benzothiazin‐4‐one 2,2‐dioxide has been developed. This general method offers a more facile entrance into the 2,1‐benzothiazine 2,2‐dioxide heterocyclic system than was heretofore available. Preparation of several 3‐carbox‐anilides was accomplished by interaction of this ring system with various isocyanates. The resulting carboxanilides are moderately strong, enolic acids.
Polyimidazopyrrolone model compounds
Authors: Young Philip R.
Published: March 2009

The model reactions between phthalic anhydride and o‐phenylenediamine were studied under conditions analogous to the polymerization and post cyclization of dianhydrides with bis(o‐diamines) to form polyimidazopyrrolones (Pyrrones). The route from the initial amide‐acid‐amine to the tetracyclic Pyrrone model when the reactions are conducted in aprotic solvents is highly competitive between isolatable benzimidazole‐acid and imide‐amine intermediates. Solid‐state thermal conversion of the amide‐acid‐amine affords a unique dimeric species containing amide, imide, and benzimidazole functions. It was confirmed that melt techniques lead to disproportionation products. The application of these findings to related polymer synthesis is discussed.
Synthesis of 7,8‐dihydroxychlorpromazine and analogs
Authors: Lee Fred G. H. , Suzuki Joseph , Dickson Donald E. , Manian Albert A.
Published: March 2009

7,8‐Dihydroxy derivatives of chlorpromazine, promazine, phenothiazine, and 7‐methoxy‐8‐hydroxychlorpromazine and its nor1analog were prepared through multi‐step syntheses. Structures were confirmed by chemical and spectroscopic evidence. The unusual nmr spectral shifts in several of these compounds are discussed.
Synthetic studies of potential antimetabolites. XIII. Synthesis of 7‐amino‐3‐β‐d‐ribofuranosyl‐3H‐imidazo[4,5‐b] pyridine (1‐deazaadenosine) and related nucleosides
Authors: Itoh Tokuo , Kitano Shigeru , Mizuno Yoshihisa
Published: March 2009

7‐Amino‐3‐β‐D‐ribofuranosyl‐3H‐imidazo[4,5‐b]pyridine (III, 1‐deazaadenosine) was synthesized in 32% yield from the diacetyl derivative prepared from 7‐aminoimidazo[4,5‐b ]pyridine (1‐deazaadenine) and 1,2,3,5‐tetra‐O‐acetyl‐β‐D‐ribose by the fusion method. A synthesis of 7‐amino‐4‐b̊‐D‐ribofuranosyl‐4H‐imidazo[4,5‐b]pyridine (IV) was also achieved.
Nucleophilic displacements on polyhalogenated heterocyclic N‐methoxy methyl sulfates
Authors: Bublitz D. E.
Published: March 2009

N‐Methoxy methyl sulfates of 2,3,4,5‐ and 2,3,5,6‐tetrachloropyridine, 3,4,5‐ and 3,4,6‐trichloropyridazine, pentachloropyridine, and tetrachloropyridazine have been prepared. Their reactions with water and aqueous potassium cyanide have been investigated.
Reissert compound studies. Cyclization of N‐(ω‐chloroalkanoyl)reissert compounds
Authors: Gibson Harry W. , Chesney Dennis K. , Popp Frank D.
Published: March 2009

Treatment of 2‐(4‐chlorobutanoyl)‐ and 2‐(5‐chloropentanoyl)‐1, 2‐dihydroisoquinaldonitrile with sodium hydride gave rise to tricyclic benzoquinolizone and azepino[1,2‐α]isoquinoline derivatives. A similar reaction was observed in the quinoline series. Several reactions of 1,2,3,4‐tetrahydro‐4‐oxo‐11bH‐benzo[α]quinolizine‐11b‐carbonitrile are reported.
On the mechanism of the 1,2‐cycloaddition of azobenzenes to ketenimines
Authors: Barker Marvin W. , Jones Raymond H.
Published: March 2009

The 1,2‐cycloaddition of unsymmetrical azobenzenes has been found to be stereoselective and the rate is essentially solvent independent. These observations lead to the postulation of a near concerted process which encounters a steric effect after alignment.
The mass spectra of small‐ring heterocycles. III. Aroylaziridines
Authors: Cromwell Norman H. , Woller Paul B. , Baumgarten Henry E. , Parker Richard G. , Minden David L. Von
Published: March 2009

The mass spectra of cis‐trans isomeric aroylaziridines are presented. Attempts to extend the method for distinguishing between cis and trans isomers previously established for aroylazetidines are described and the results rationalized. A simple fission of the 1‐alkylnitrogen bond is described and detailed fragmentation mechanisms are presented and discussed.
Mass spectra of some 1,2,4‐thiadiazoles
Authors: Potts K. T. , Armbruster R.
Published: March 2009

Substituted 1,2,4‐thiadiazoles were found to undergo fragmentation by loss of RCN from the molecular ion with both 3‐ and 5‐substituents being involved to some extent. This was followed by loss of sulfur to yield a nitrilium ion. With 5‐hydrazino substituents, hydrogen transfer was observed from the substituent to a ring nitrogen atom.
The preparation of 3‐aminoanthyridine
Authors: Carboni S. , Da Settimo A. , Bertini D. , Ferrarini P. L. , Livi O. , Tonetti I.
Published: March 2009

Nitration of anthyridine‐2,6‐dione (I) gave 7‐nitroanthyridine‐2,6‐dione (II). Treatment of this compound with phosphorus pentasulfide afforded 7‐aminoanthyridine‐2,6‐dithione (III). Desulfurization of the thioderivative III with Raney Nickel and subsequent aromatization of 3‐amino‐5,10‐dihydroanthyridine (VI) in boiling nitrobenzene, gave 3‐aminoanthyridine (VII) in satisfactory yield. The structure of 3‐aminoanthyridine was demonstrated and its physico‐chemical features are not in agreement with that previously reported in literature. The preparation of 3‐aminoanthyridine‐5‐one (XII) is also described.
Synthesis of 8,9‐dialkoxy‐substituted tetrahydrobenz[h] isoquinolines
Authors: Zee‐Cheng Kwang Y. , Nyberg Wayne H. , Cheng C. C.
Published: March 2009

6,7‐Dimethoxy‐2‐naphthylethylamine, prepared by the diborane reduction of 6,7‐dimethoxy‐2‐naphtlialeneacetamide, underwent a Pictet‐Spengler cyclization to form 8,9‐dimethoxy‐1,2,3,4‐tetrahydrobenz[h]isoquinoline. This compound is identical with that obtained by reduction of the corresponding dihydrobenzisoquinoline prepared from formamide cyclization. 6,7‐Dialkoxy‐2‐naphthaleneacetic acids, the key intermediates for the preparation of these amides, were obtained from 6,7‐dialkoxy‐2‐acetonaphthones by a modified Willgerodt reaction.
Alkyl N‐methylfuroxanylcarbamates. Synthesis and structure. II
Authors: Gasco A. , Mortarini V. , Ruà G. , Menziani E.
Published: March 2009

From 3‐methyl‐4‐furoxancarboxylic acid hydrazide and 4‐methyl‐3‐furoxancarboxylic acid hydrazide the corresponding azides have been synthesized. 3‐Methyi‐4‐furoxancarboxylic acid azide normally underwent the Curtius reaction to give the expected carbamic acid derivative. The degradation of 4‐methyl‐3‐furoxancarboxylic acid azide led to the N‐(4‐methylfuroxan‐3‐yl)‐carbamic acid derivative at low temperatures and to N‐(3‐methylfuroxan‐4‐yl)carbamic acid derivative at higher temperatures.
On the nitration of 2‐benzylthiophene and the spectroscopic behaviour of nitro‐2‐benzylthiophenes
Authors: Arcoria A. , Maccarone E. , Musumarra G. , Romano G.
Published: March 2009

Nitration of 2‐benzylthiophene with nitric acid (molar ratio 1:1) in acetic anhydride gave only nitro‐2‐benzylthiophenes, indicating the benzene ring is unreactive to this electrophilic substitution. The main reaction product was 2‐benzyl‐5‐nitrothiophene (about 87%) the amounts of the 3‐nitro and 4‐nitro isomers were about 10% and 3%, respectively. These percentages, determined by glc and nmr techniques, were found to be constant using various nitration conditions. The syntheses of the nitro‐2‐benzylthiophenes are described, together with some spectroscopic properties.

The uv spectra confirm that the conjugation of the nitro group in the α position is greater than in the β position. The isomer structures have been assigned by nmr chemical shifts and coupling constant of the thiophene protons. Also infrared spectra are briefly considered.
Synthesis of (±)‐laudanoeine and a study of 1‐benzyl‐3‐isoquinoione intermediates
Authors: Elliott I. Wesley
Published: March 2009

A keto acid (2) has been converted to tetrahydropapaverine and (±)‐laudanosine. Some intermediate 3‐isochromanone (3) and 3‐isoquinolone (4 and 5) derivatives have been investigated and structures assigned to these compounds from spectroscopic studies. The 3‐isoquinolone tautomer with the o‐quinonoid structure predominates over the 3‐isoquinolinol form, but the analogous oxygen derivative has preferentially a stilbene structure (3) with an intact benzene system.
Synthesis of 3‐substituted N‐aminopyridinium salts
Authors: Tamura Yasumitsu , Miki Yasuyoshi , Honda Toshiko , Ikeda Masazumi
Published: March 2009

Ring opening of N‐(2,4‐dinitrophenyl)pyridinium chlorides with hydrazine followed by recyclization resulted in the formation of N‐aminopyridinium salts. The scope of this reaction sequence was determined and several new 3‐substituted N‐aminopyridinium salts were prepared.
Endocyclic vs exocyclic olefin formation from 4‐piperidones via the wittig reaction
Authors: Borne Ronald F. , Aboul‐Enein Hassan Y.
Published: March 2009

The reaction of 1‐methyl‐4‐piperidone and 1‐benzoyl‐4‐piperidone with triethyl phosphono‐acetate in the presence of excess base yields both the endocyclic and exocyclic olefins. However, treatment of 1‐methyl‐4‐piperidone with diethyl cyanomethylphosphonate, even in the presence of excess base, yielded only the exocyclic olefin. Factors affecting isomer distribution during the course of the reaction are presented. The isolation of an exocyclic tetrahydropyridine from the sodium borohydride reduction of the methiodide of 4‐pyridylacetonitrile is reported.
The crystals and molecular structure of 1,1,4,4‐Tetraphenyl‐2,5‐di‐(t‐butyl)‐1,4‐diphosphoniacyclohexadiene‐2,5‐dichloride
Authors: Cheung L. D. , Trefonas L. M.
Published: March 2009

The crystal and molecular structure of the title compound has been determined by single crystal, x‐ray diffraction techniques. The compound crystallizes in a monoclinic space group of C2/c symmetry with four molecules in a unit cell of dimensions a = 24.578(1), b = 10.503(1), c = 17.579(1) Å and (3 = 1.30.93 ± .01°. The unit cell also contains two waters of crystallization which are involved in hydrogen bonds to the chloride ions. The central ring has been shown to be a diene which resides in a boat conformation defined by dihedral angles of 157°. The structure has been refined to a value of R = 0.08 using the 1535 statistically significant reflections measured out ot a 2θ value of 140°.
Naphthyridine chemistry. XVI. A literature correction —The preparation of 2,4‐Dimethyl‐7‐ethoxy‐1,8‐naphthyridine 1‐Oxides
Authors: Vandahm Richard A. , Pokorny David J. , Paudler William W.
Published: March 2009

The N‐oxidation of 2,4‐dimethyl‐7‐ethoxy‐1,8‐naphthyridine has been shown to afford the 1‐oxide rather than the 1,8‐dioxide as reported by others.
Reactions of substituted pyridines and their N‐oxides with ethanolic sodium hydroxide and various alkoxides
Authors: Muth Chester W. , Darlak Robert S. , Patton Jesse C.
Published: March 2009

2‐Benzoylpyridine 1‐oxide with ethanoiic sodium hydroxide yielded acyl nucleophilic displacement products and a redox product, 2‐(α‐hydroxybenzyl)pyridine. 3‐Benzoylpyridine 1‐oxide under the same conditions yielded only a reduction product, 3‐(α‐hydroxybenzyl)‐pyridine 1‐oxide, whereas 4‐benzoylpyridine 1‐oxide yielded only a redox product, 4‐(α‐hydroxy‐benzyl)pyridine. The redox reaction which is promoted by base occurs with an α‐hydroxybenzylpyridine 1‐oxide which results from a carbonyl reduction of the starting material. The benzoyl‐pyridine 1‐oxides reacted qualitatively the same with sodium ethoxide or isopropoxide as they did with ethanoiic sodium hydroxide, but they reacted differently with potassium t‐butoxide or aluminum isopropoxide. The cyano‐ and benzenesulfonyl‐pyridine 1‐oxides reacted with ethanolic sodium hydroxide to yield pyridinecarboxylic acids and 1‐hydroxypyridones, respectively.
Synthesis of a 2‐Methyl‐4‐sulfanilamido‐s‐triazine derivative
Authors: Kametani Tetsuji , Okui Kiyoshi , Koizumi Masuo
Published: March 2009

An attempt to obtain 2‐methyl‐4‐sulfanilamido‐s‐triazine (XXI) by condensation of 2‐amino‐4‐methyl‐s‐triazine (II) with p‐acetamidobenzenesulfonyl chloride (III) in pyridine and in benzene containing trimethylamine gave instead the unexpected products, guanidine N‐acetylsulfanilate (IV) (after hydrolysis) and N1,N1‐dimethylsulfanilamide (V), respectively. On the other hand, 2‐methyl‐4‐methylthio‐6‐sulfanilamido‐s‐triazine (XIX) was obtained from 4,6‐dimethylthio‐s‐triazine (XVII), but the reduction of XIX with Raney nickel in aqueous sodium hydroxide solution also gave an unexpected compound, sulfaguanidine (XX).
The preparation of 2‐Chloroformyl‐3‐phenylthiazolo[3.2‐a] pyridiniuin chlorides from cinnamic acids, pyridine and thionyl chloride
Authors: Wright W. B. , Brabander H. J.
Published: March 2009

2‐Chloroformyl‐3‐phenylthiazolo[3.2‐a]pyridinium chlorides are among the by‐products obtained when 3‐chlorobenzo[b]thiophene‐2‐earbonyl chlorides are prepared by the reaction of cinnamic acids with thionyl chloride and pyridine.
Synthesis of 1,2,3‐triazole nucleosides via the acid‐catalyzed fusion procedure
Authors: Lehmkuhl Frank A. , Witkowski Joseph T. , Robins Roland K.
Published: March 2009

The acid‐catalyzed fusion of methyl 1,2,3‐triazole‐4‐carboxylate, 4‐cyano‐1,2,3‐triazole, and 4‐nitro‐1,2,3‐triazole with an acylated ribofuranose provided the corresponding 2‐β‐D‐ribo‐furanosyl‐4‐substituted‐1,2,3‐triazoles along with the isomeric 1‐β‐D‐ribofuranosyl‐4‐substituted‐1,2,3‐triazoles. The structures of these nucleosides were assigned on the basis of their nmr spectra. The synthesis of 2‐β‐D‐ribofuranosyl‐1,2,3‐triazole‐4‐carboxamide from both the corresponding methyl ester and cyano nucleosides is described. The cyano nucleosides were utilized to prepare 2‐β‐D‐ribofuranosyl‐1,2,3‐triazole‐4‐thiocarboxaḿide and 1‐β‐D‐ribofuranosyl‐1,2,3‐triazole‐4‐thiocarboxamide. Reduction of the 4‐nitro‐1,2,3‐triazole nucleosides provided 4‐amino‐2‐β‐D‐ribofuranosyl‐1,2,3‐triazole and the isomeric 4‐amino‐1‐β‐D‐ribofuranosyl‐1,2,3‐triazole. The acid‐catalyzed fusion procedure with 1,2,3‐triazole afforded 1‐β‐D‐ribofuranosyl‐1,2,3‐triazole and 2‐β‐D‐ribofuranosyl‐1,2,3‐triazole.
Derivatives of 10,11‐dihydro‐5H‐dibenzo[a,d]cycloheptene and related compounds VII. Improved syntheses of 11‐h‐benzo[5, 6] cyclohepta‐[1,2‐c] pyridin‐11‐one
Authors: Villani Frank J. , Wefer Elizabeth A. , Mann Thomas A. , Mayer Joseph , Peer Lydia , Levy Alfred S.
Published: March 2009

An improved synthesis of the title compound is described. The base catalyzed condensation of 4‐methylnicotinonitrile with benzaldehyde resulted in the isolation of trans‐4‐styrylnicotin‐amide (2a) in high yield. Hydrolysis to the acid and heating the acid 3a with polyphosphoric acid (ppa) gave the title compound 1a in good yields. Even higher yields of 1a were obtained in the presence of catalytic quantities of selenium. Also described are two other syntheses of the title compound as well as the preparation of a series of compounds related to 2a (Table I).
Synthesis of 4,5‐dihydro‐2,4‐benzoxazepin‐3( 1H)ones and 1,3,4,5‐tetrahydro‐2,4‐benzoxazepines
Authors: Pifferi Giorgio , Fontanella Luigi , Occelli Emilia , Monguzzi Riccardo
Published: March 2009

o‐ Aminomethylbeiizyl alcohols (X) easily cyclize with phosgene in an aqueous alkaline medium to form 4,5‐dihydro‐2,4‐benzoxazepin‐3(1H)ones (IV) and with aldehydes in acidic conditions to yield 1,3,4,5‐tetrahydro‐2,4‐benzoxazepines (V). The characteristics and chemical behaviour of these new heterocyclic ring systems are reported.
Intramolecular diels‐alder reactions. IX. Syntheses of N‐benzylcyclolignan lactams
Authors: Klemm L. H. , Mcguire T. M.
Published: March 2009

Four bis‐unsaturated N‐benzyl amides of the type where (C2) and (C2)' are variously trans‐CHCH and CC groups, were synthesized and refluxed in acetic anhydride. Three of them cyclized to form N‐benzylcyclolignan lactams by intramolecular Diels‐Alder processes. In one case [(C2)  CC, (C2)'  trans‐CHCH] the (C2) unit functioned as the dienophilic moiety.
Synthesis of azepinoquinazoloncs from 2‐methyl‐3‐(o‐tolyl)‐4‐quinazolone
Authors: Taylor John H. , Harrison Derek R. , Fried Ferdinand
Published: March 2009

Some new azepinoquinazolones were synthesized from 2‐methyl‐3(o‐tolyl)‐4(3H)quinazolone (metliaqualone )as potential hypnotic agents. Methaqualone (I) reacted with dimethyl acetylene‐dicarboxylate (dmad) to give the azepinoquinazolone (II) which on treatment with PPA gave the pentacyclic ketone (V). Subsequent sodium borohydride reduction of the ketone (V) gave the fused azepine (VIa). Reaction of the azepinoquinazolone (II) with formic acid resulted in cleavage of the quinazolone nucleus to give the azepine (VIII). None of the compounds synthesized exhibited significant hypnotic activity.
The reactions of some pyranylideneiminium salts with amines. Part 1
Authors: Van Allan J. A. , Reynolds G. A. , Maier D. P. , Chang S. Chie
Published: March 2009

The iminium salt, N,N‐dimethyl‐N‐[2‐(2,6‐diphenyl‐4H‐pyran‐4‐ylidene)ethylidene]iminium perolilorate (1), reacts with secondary amines, such as piperidine, by exchanging the dimethyl‐amino function for a piperidine. Primary amines react with 1 to give 1‐alkyl‐2‐phenyl‐4‐phenacylidene‐1,4‐dihydropyridines. The bisiminium salt, N,N,N',N' ‐tetramethyI‐N,N'‐[2‐(2,6‐diphenyl‐4H‐pyran‐4‐ylidene)‐1,3‐propanediylidene]bis(iminium perchlorate) (2), reacts with ammonia to give 3,6‐diphenylcopyrine and with primary amines to give the corresponding N,N' ‐dialkyl quaternary copyrines. The salt 2 reacts with secondary amines with exchange of the dimethylamino groups of 2 by the secondary arnine and addition of the amine at the 2‐position of the pyran ring.
The reactions of some pyraiiylideneiminium salts with amines. II
Authors: Van Allan J. A. , Chang S. Chie , Reynolds G. A.
Published: March 2009

The iminium salt, N,N‐dimethyl‐N‐[2‐(2‐phenyl‐4H‐l‐benzopyran‐4‐ylidene)ethylidene] imin‐ium perchlorate (3), reacts with secondary amines by exchanging the dimethylimino group for the added amine. Primary amines also reacted with 3 in the same manner. The bis iminium salts, N,N,N',N'‐tetramethyl‐N,N'‐[2‐(2‐phenyl‐4H‐l‐benzopyran‐4‐ylidene)‐1,3‐propanediylidene]‐bis(immium perclilorate) (4) and the corresponding thiapyran derivative (5), react with ammonia to give 5‐dimethylamino‐2‐phenyl‐5H‐1‐benzopyrano[3,4‐c]pyridine (10) and the thia analog 11. The reactions of 4 and 5 with primary amines give 3‐alkyl‐5‐dimethylamino‐2‐phenyl‐5H‐l‐beiizopyrano[3,4‐c]pyridinium perclilorate salts or the corresponding thiapyrano compounds. Compounds 4 and 5 react with secondary amines by exchanging the dimethylimino groups with the secondary amine and addition of the amine at the 2‐position of the pyran or thiapyran ring.
Synthesis of phenylated phthalimides. The diels‐alder reaction of tetraphenylcyclopentadienone with maleimides
Authors: Harris Frank W. , Norris Steve O.
Published: March 2009

A series of phenylated dihydrophthalimides has been synthesized by the Diels‐Alder reaction of tetraphenylcyclopentadienone with maleimide, N‐phenylmaleimide, and N,N'‐o‐, ‐m‐, and ‐p‐phenylenedimaleimide. Subsequent dehydrogenation of these compounds yielded the corresponding phenylated phthalimides. These phthalimides were also obtained in one step when the initial reactions were carried out in refluxing nitrobenzene.
Synthesis of 3‐aryl‐7‐nitro‐3,4‐dihydroisocoumarins from 4‐nitrohomophthalic acid
Authors: Barry Roger D. , Balding Richard A.
Published: March 2009

4‐Nitrohomophthalic acid reacts with aromatic aldehydes in the presence of piperidine to yield 3‐aryl‐7‐nitro‐3,4‐dihydroisocoumarins. Under the same conditions, homophthalic acid yields stilbene‐α,2‐dicarboxylic acids.
Organosilicon compounds XVII. Introduction of the dialkyl phosphonate and dialkyl thiophosphonate moieties on an organosilicon substituted heterocyclic system
Authors: Thames Shelby F. , Edwards Laroy H. , Jacobs Thornton N. , Grube Paul L. , Pinkerton Frank H.
Published: March 2009

A number of new dialkyl 2‐(5‐trisubstitutedsilyl)thienylphosphonates and thiophosphonates as well as dialkyl 2‐(5‐trisubstitutedsilyl)furylphosphonates and thiophosphonates were prepared via reaction of the 5‐(trisubstitutedsilyl)‐2‐lithiothiophenes and furans with dialkyl chloro‐phosphate and dialkyl chlorothiophosphate. Moreover, some diethyl 2‐[5‐(trisubstitutedsiIyl)‐2‐thienyl] ethyl thiophosphates are reported.
Studies on the syntheses of heterocyclic compounds. CDXCI pyrimidine derivatives V. Abnormal condensation products of 4‐amino‐6‐chloro‐2‐methoxypyrimidine with p‐nitrobenzenesulfonyl chloride
Authors: Okui Kiyoshi , Ito Kiyohiko , Koizumi Masuo , Fukumoto Keiichiro , Kametani Tetsuji
Published: March 2009

Condensation of 4‐amino‐6‐chloro‐2‐methoxypyrimidine (I) with p‐nitrobenzenesulfonyl chloride (II) gave, in addition to 6‐chloro‐2‐methoxy‐4‐(p‐nitrobenzenesulfonamido)pyrimidine (III), two abnormal by‐products, the structures of which were assigned as 1‐[2‐methoxy‐4‐(p‐nitrobenzenesulfonamido)pyrimidine‐6‐yl]pyridinium N,N‐betaine (IV) and N‐(p‐nitrobenzene‐sulfonyl)‐β‐ureido‐β‐pyridinium acrylamide N,N‐betaine (V).
Photoelimination reactions of N‐heteroaromatic compounds
Authors: Stermitz F. R. , Huang W. H. , Blythin D. J. , Hoeft A. , Kim D. K. , O'Donnell C. M.
Published: March 2009

N‐Heteroaromatic compounds substituted with a side chain next to the nitrogen and bearing a hydrogen gamma to the ring, undergo a photoelimination reaction to yield the methyl‐substituted heterocycle and an alkene (if the gamma hydrogen is on a side chain carbon) or an aldehyde (if the gamma hydrogen is on a side chain oxygen). The reaction has been shown to occur with substituted isoquinolines, plienanthridines, pyridines and pyrazines.
Steroids. Synthesis of 1,4‐oxazine derivatives of estrone
Authors: Roy Sunil K.
Published: March 2009

Estratrieno[3,2‐b]‐1,4‐oxazin‐3′‐one (V) and estratrieno[3,4‐b]‐1,4‐oxazin‐3′‐one (VI) have been converted to the corresponding amidines. The tautomerism of the thiones and the amidines are discussed.
Synthetic studies on pyrroloquinolines. II. Studies on the syntheses and chemical properties of 1H‐pyrrolo[2,3‐b] quinolmes
Authors: Tanaka Tadasu , Iwakuma Takeo , Wagatsuma Mitsuyoshi , Iijima Ikuo
Published: March 2009

This paper describes the syntheses and the properties of 1H‐pyrrolo[2,3‐6]quinolines derived from 2,3‐dihydrofuro[3,2‐c]quinolines or 3‐(β‐chloroethyl)‐2,4‐dichloroquinolines. The discrepancy on the physical data of 1H‐pyrrolo[2,3‐b]quinoline between our product and Perkin's previously reported product is also discussed.
Studies on the syntheses of heterocyclic compounds. Part CDXCVII. Total syntheses of (±)‐cryptaustoline and (±)‐thaliporphine by the benzyne reaction
Authors: Kametani Tetsuji , Fukumoto Keiichiro , Nakano Takuo
Published: March 2009

The indisputable benzyne reaction of 1‐(5‐bromo‐3,4‐dimethoxybenzyl)‐1,2,3,4‐tetrahydro‐7‐hydroxy‐6‐metlioxy‐2‐methylisoquinoline (II) with sodium amide in liquid ammonia afforded the following compounds, (±)‐cryptaustoline iodide (VI), (±)‐thaliporphine (VIII), 1 ‐(3,4‐dimeth‐oxybenzyl)‐ (III), and 1 ‐(2‐amino‐4,5‐dimethoxybenzyl)‐l,2,3,4‐tetrahydro‐7‐hydroxy‐6‐meth‐oxy‐2‐methylisoquinoline (IV).
Synthesis of diazasteroids II. Synthesis of 8,11‐diaza‐2,3‐dimethoxygona‐1, 3,5 (10), 9 (11)‐tetraene
Authors: Nagata Masanori , Goi Masami , Matoba Katsuhide , Yamazaki Takao , Castle Raymond N.
Published: March 2009

Homoveratrylamine was condensed with 1‐cyanocyclopentene to afford the corresponding 2‐cyano‐N‐(3,4‐dimethoxyphenethyl)cyclopentylamine (III), which was ethoxycarbonylated with ethyl chlorocarbonate to give the trans‐urethan (IVt) (major product) and the cis‐urethan (IVc) which could be separated through a silica gel column. The cis‐urethan was converted to the trans‐urethan by the action of a catalytic amount of sodium ethoxide. Based upon general considerations of nucleophilic addition such as the Michael type reaction, the physical data obtained, and the difference in ease of cyclization of the 2‐aminomethyl‐N‐ethoxycarbonyl‐. N‐homoveratrylcyclopentylamines (Vt and Vc) to the corresponding cyclic ureas (Vlt and VIc), it was concluded that the major product was the trans and the minor the cis isomer.

The cyclized compounds, Vlt and VIc, were subsequently submitted to the Bischler‐Napieralski reaction furnishing the corresponding isoquinoline derivatives respectively. Thus the authors established a skeletal synthesis of the title compound, a 8,11‐diazasteroid, and its stereochemical configuration at the C/D ring juncture was elucidated.
9‐Hydroxy‐2‐methyl‐4H‐pyrido[1,2‐α] pyrimidin‐4‐one and its derivatives
Authors: Yale Harry L. , Sheehan John T.
Published: March 2009

2‐Amino‐3‐(o‐bromobenzyloxy)pyridine (1) and ethyl acetoacetate gave 9‐(o‐bromobenzyl‐oxy)‐2‐methyl‐4H‐pyrido[1,2‐α]pyrimidin‐4‐one (2) in 2% yield. When 1 and methyl β‐amino‐crotonate (3) were reacted, benzyl ether cleavage occurred and the products were 9‐hydroxy‐2‐methyl‐4H‐pyrido[1,2‐α]pyrimidin‐4‐one (4) and its ammonium salt (5). These observations led to an alternative synthesis in which 2‐amino‐3‐pyridinol (6) and either 3 or methyl acetoacetate, (8) in diethylbenzene at 185° gave 4 in 86 and 87% yields, respectively, and the anion of 4 and o‐bromobenzyl bromide gave 2 in 61% yield. Even in diethylbenzene at 185°, 1 and 8 gave only trace amounts of 2. Thus, o‐bromobenzylation of the 3‐hydroxyl group in 6 markedly decreased the reactivity of the amino group in 6 toward reactions with acetoacetic esters.
Studies on the bromination of pyrimidine. A facile synthesis of 5‐bromopyrimidine
Authors: Kress Thomas J. , Moore Larry L.
Published: March 2009

Three methods for hromination of pyrimidine were investigated: (a) the bromination of pyrimidine hydrochloride in aromatic solvents, (b) the vapor phase bromination of pyrimidine, and (c) the pyrolysis of pyrimidine hydrochloride perbromide. The addition of bromine to a slurry of pyrimidine hydrochloride in nitrobenzene proved to be superior and afforded excellent yields of 5‐bromopyrimidine.
Studies in the claisen rearrangement. Part XII . Synthesis of benzofuro[3,2‐c] [l]‐6a,lla‐dihydro‐lla‐methylbenzopyrans from 1,4‐diaryloxy‐2‐butynes
Authors: Majumdar K. C. , Thyagarajan B. S. , Balasubramanian K. K.
Published: March 2009

Successful Claisen rearrangement of a number of 1,4‐diaryloxy‐2‐butynes is reported. The products of such a rearrangement are the benzofuro[3,2‐c]benzopyrans. This novel rearrangement offers a facile synthetic route to tetracyclic derivatives resembling the naturally occurring pterocarpans.
The synthesis of optically active 5‐phenylhydantoins
Authors: Dudley Kenneth H. , Bius Daniel L.
Published: March 2009

A number of reagents have been examined for effecting the conversion of an optically pure 2‐phenylhydantoic acid to an optically active 5‐phenylhydantoin. Trifluoroacetic anhydride (TFAA method) and dilute hydrochloric acid (acid‐catalysis method) proved to be the reagents of choice. The dependence of the kinetics of racemization of the 5‐phenylhydantoin system on temperature has been studied in dilute hydrochloric acid solution to support the conclusion that 5‐phenylhydantoins prepared by the acid‐catalysis method are nearly, if not entirely, optically uniform.
Synthetic studies in the lsoxazoko[4,5‐b] pyrazine system
Authors: Abushanab E. , Lee D. Y. , Goodman L.
Published: March 2009

The synthesis of 3‐methylisoxazolo[4,5‐b]pyrazine (5) and its 7‐oxide (6) is reported. Nitration of 6 furnished the 6‐nitro derivative (8) while reaction with phosphoryl chloride provided the chloro derivative (7). Efforts to functionalize the methyl group in 5 were not successful.
Nmr spectral characteristics of N‐H protons in purine derivatives
Authors: Twanmoh Li‐Ming , Wood Harry B. , Driscoll John S.
Published: March 2009

Proton chemical shifts are examined in a series of twelve purine and three 5‐azapurine derivatives. The assignment of N‐H signals in the xanthine and thioxanthine series, as well as the effects of moisture, concentration and temperature on the N‐H and C‐H nmr spectral characteristics are discussed.
Overcrowded molecules. V. 3,10‐dimethyl‐1,12‐bis(2‐pyridyl)benzo[c] phenanthrene‐2,11‐diol
Authors: Fields D. L. , Regan T. H.
Published: March 2009

The bis ketene acetal adduct of 4a,10a‐diazoniaanthra[1,2‐α]anthracene diperchlorate (10) was used to prepare the highly overcrowded benzo[c]phenanthrene 2 by a known procedure. Its oxidation with cupric chloride provided the isoxazolium zwitterion, 3, via an intramolecular cyclization.
On the reactions of β‐ketoesters with 2,3‐diaminopyridine and its derivatives
Authors: Israel Mervyn , Jones Lynne C.
Published: March 2009

Studies in these laboratories and elsewhere on the condensation of β‐ketoesters with unsym‐metrical o‐diamines have thus far failed to explain the factors which govern the direction of cyclization in these reactions. Various additional diamine‐ketoester condensations have been studied and the results compared in an attempt to develop generalizations of predictive value regarding the direction of ring closure to form diazepinones. The following condensation reactions are described: 2,3‐diaminopyridine with 2‐ethoxycarbonylcyclohexanone and with ethyl α‐methylacetoacetate, 5‐bromo‐2,3‐diamino‐4‐methylpyridine with ethyl acetoacetate, 3‐amino‐2‐anilinopyridine and 3‐amino‐2‐methylaminopyridine with ethyl acetoacetate, and N‐methyl‐o‐phenylenediamine with ethyl acetoacetate.
Benzo[b] thiophene derivatives. XIX. The sulfur isosteres of psiloein and related isomers
Authors: Campaigns K. , Rogers R. B.
Published: March 2009

The sulfur analog of psilocin, 3‐(β‐dimethylaminoethyl)‐4‐hydroxybenzo[b ]thiophene, and some O‐methylated and N‐demethylated isomers have been synthesized for pharmacological evaluation. Preliminary tests indicate central nervous system (CNS) activity, but weak pressor activity.
3(2H)isoquinolones. 2. Studies on the structure and formation of aminonaphthols obtained in the preparation of 3(2H)isoquinolones
Authors: Kreighbaum W. E. , Kauanaugh W. F. , Comer W. T.
Published: March 2009

The reaction of a 2‐acylphenylacetic acid derivative (I) with primary amines in glacial acetic acid produces novel, colorless aminonaphthols (III) which are isomeric with the brilliant yellow 3(2H)isoquinolones (II) obtained in the same reaction. A combination of chemical and spectral techniques allowed identification of the isomers as derivatives of 4‐amino‐2‐naphthol. A plausible mechanism of formation of aminonaphthols versus 3(2H)isoquinolones is discussed and supported by chemical synthesis of N‐substituted 2‐aeylphenylacetamides (VIII) and a 1,4‐dihydro‐1‐hydroxy‐3(2H)isoquinolone derivative (IX).
Synthesis and characterization of isomeric cis‐ and trans‐pyrrone model compounds
Authors: Young Philip R.
Published: March 2009

Isomeric cis‐ and trans‐imidazopyrrolones, obtained from the reaction of pyromellitic di‐anhydride and o‐phenylenediamine, were prepared as models for pyrrone polymers. The characterization of these model compounds, which represent the repeat unit of the completely cyclized polymer, provided information which could not be obtained by studying the polymer itself. Isomerism was proven by the nuclear magnetic resonance spectra of soluble ester‐benzimidazole derivatives. This study indicated that a single band around 1755 cm−1 should appear in the infrared spectrum of the completely cyclized polymer. The high melting points of the model imidazopyrrolones indicate the extreme thermal stability to be anticipated from perfectly formed pyrrone polymers.
Heterocyclic derivatives of naphthalene‐1,8‐dicarboxylic anhydride. Part I. Nitro‐7H‐benzimidazo[2,1‐a]benz[de]isoquinolin‐7‐ones
Authors: Grayshan P. H. , Peters Arnold T.
Published: March 2009

Condensation of o‐phenylenediamine with 2‐, 3‐ and 4‐nitronaphthalene‐1,8‐dicarboxylic anhydrides gives, in each case, an isomer mixture. Separation of the mixtures into the six isomeric mononitro‐7H‐benzimidazo[2,1‐a]benz[de]isoquinolin‐7‐ones is described and the isomers characterised in respect of previously reported data on some isomers; ir and mass spectrum data are reported, the latter showing fragmentation ions which may be used in characterising dyes based on this chromophore. Other new derivatives of 7H‐benzimidazo[2,1‐a]benz[de]isoquinolin‐7‐one are also described.
Synthetic studies leading to DE‐ring analogs of camptothecin
Authors: Hansen John F. , Kamata Kazuyuki , Meyers A. I.
Published: March 2009

A synthetic scheme leading to an isomeric DE ring (14) of the anti‐tumor alkaloid, camptothecin, has been achieved. However, the method failed to give the correct pyridone lactone (2) found in this alkaloid.
Synthesis of 1,3,5,7‐tetraazacyclooctane derivatives
Authors: Yoshida H. , Sen G. , Thyagarajan B. S.
Published: March 2009

Tetraazaadamantane was converted under mild conditions into 1,3,5,7‐tetraazabicyclo[3.3.1]nonane derivatives. The latter were transformed selectively into 1,3,5,7‐tetraazacyclooctane derivatives avoiding the formation of 1,3,5‐triazacyclohexane compounds.
3‐Amino‐5‐phenyl‐1‐(2‐pyridyl)pyrrolidines. Synthesis and stereochemistry
Authors: Hanna Patrick E.
Published: March 2009

Stereoselective syntheses of trans‐ and cis‐3‐amino‐5‐phenyl‐1‐(2‐pyridyl)pyrrolidine (21 and 24) are reported. Evidence for the relative stereochemistries of 21 and 24 was obtained by preparation of the bicyclic lactams exo‐ and endo‐7‐phenyl‐1,4‐diazabicyclo[3.2.1.]octan‐3‐one (16 and 19) from precursors of 21 and 24.
Intermediaires dans le rearrangement de dimroth d'imidazo[1,2‐a]pyridines
Authors: Jacquier Robert , Lopez Hélène , Maury Georges
Published: March 2009

Les imidazo [1,2‐a] pyridines subissent le réarrangement de Dimroth en milieu aqueux basique si le noyau est active par des groupements nitro en position 6 ou 8. La réaction peut ětre limitée à la formation de composés intermédiaires de ce réarrangement qui ont été étudiés en RMN notamment.
Sur une prétendue forme NH stable d'une pyrazoline‐3
Authors: Baumes Raymond , Elguero José , Jacquier Robert , Tarrago Georges
Published: March 2009

Selon Wittig et Hutchison (1) la reduction d'un pyrazole N‐substitue par l'hydrure d'aluminum lithium conduit a une pyrazoline‐3 N(H)1 stable.

Nous montrons, en fait, que cette reaction s'effectue par reduction d'un isopyrazole en pyrazoline‐2; il est alors necessaire de reconsiderer la transposition des pyrazolènines qui, dans certains cas, conduit aux isopyrazoles et non aux pyrazoles.
The synthesis of some 4H‐pyrimido[2,1‐b]benzothiazol‐4‐ones
Authors: Alaimo Robert J.
Published: March 2009

A series of 8‐substituted and 7,8‐disubstituted‐4‐oxo‐3‐(4H‐pyrimido[2,1‐b]benzothiazole)carboxylic acids and esters including a 9‐aza analog were synthesized from substituted 2‐aminobenzothiazoles and diethyl ethoxymethylenemalonate. The 9‐aza analog, ethyl 8‐methoxy‐4‐oxo‐3‐(4H‐pyrido[3′,2′:4,5]thiazolo[3,2‐a]pyrimidine)carboxylate (56), represents the first preparation of this new heterocyclic ring. These compounds were examined for antiparasitic activity, however, no significant activity was detected.
The polar nature of 2,1,3‐benzoxadiazole, ‐benzothiadiazole, ‐benzoselenadiazole and derivatives as determined by their electric dipole moments
Authors: Tobiason F. L. , Huestis Laurence , Chandler Chris , Pedersen Svend E. , Peters Phillip
Published: March 2009

Permanent electric dipole moments have been determined in benzene solutions at 25° for the oxygen, sulfur, and selenium series of 2,1,3‐benzodiazoles. The derivatives studied contained 4, 5, and 6 substituted methyl, chloro, nitro, and amino groups. The dipole moment data of the derivatives were analyzed relative to that of the parent species which allowed deductions to be made about the mesomeric structures operating in the compounds. The mesomeric charge transfer increases regularly from the oxygen to the selenium structures, being nearly undetected in 2,1,3‐benzoxadiazole derivatives and very pronounced in the 2,1,3‐benzoselenadiazoles.
A 5‐methylthiopenicillin analog and its transformation to novel bicyclic β‐lactams
Authors: Bose Ajay K. , Fahey John L. , Manhas M. S.
Published: March 2009

Reaction of methoxyacetyl chloride with 2‐methylthio‐2‐thiazoline resulted in the stereoselective production of one isomer of 6‐methoxy‐5‐methylthiopenam which underwent rearrangement to 6‐methoxy‐7‐methylthio‐5‐oxo‐2,3,4,5‐tetrahydro‐1,4‐thiazepine when treated with trifluoroacetic acid. Subsequent thioamidation and alkylation with methyl iodide provided 5,7‐bismethylthio‐6‐methoxy‐2,3‐dihydro‐1,4‐thiazepine which reacted with methoxyacetyl chloride and triethylamine to give a novel 1,4‐thiazabicyclo[5.2.0]non‐5‐ene. Other substituted bicyclic β‐lactams of similar structure have also been synthesized.
The photo cycloaddition of alkenes to s‐triazolo[4,3‐b] and [2,3‐b]pyridazines
Authors: Bradshaw J. S. , Stanovnik B. , Tišler M.
Published: March 2009

s‐Triazolo[4,3‐b]pyridazine (I) reacted with cyclohexene under the influence of ultraviolet light to yield 4a,5,7,8,8a,9‐hexahydro‐9‐methylene‐6H‐s‐triazolo[1,5‐a]indole (IV) and 9‐cyanomethyl‐4a,5,7,8,8a,9‐hexahydro‐6H‐s‐triazolo[1,5‐a]indole (V). These products were formed by the addition of the alkene to the 1,8 positions of I with a concurrent cleavage of the N4N5 bond. Similar additions were observed with cyclopentene and 2,3‐dimethyl‐1,3‐butadiene. The isomeric s‐triazolo[2,3‐b]pyridazine (III) reacted with cyclohexene to form an isomer of IV, 4a,5,7,8,8a,9‐hexahydro‐9‐methylene‐6H‐s‐triazolo[4,3‐a]indole (XV) and two [2 + 2] cycloadducts (XVI and XVII).
The preparation of 5‐(2‐bromoethyl)‐2‐iminooxazolidines via the von braun cyanogen bromide reaction
Authors: Fielden Marvel L.
Published: March 2009

The reaction of certain 1‐alkyl‐3‐pyrrolidinols with cyanogen bromide in ether solution produced 3‐alkyl‐5‐(2‐bromoethyl)‐2‐iminooxazolidines. 5‐(2‐Bromoethyl)‐2‐ethyl‐2‐imino‐5‐phenyloxazolidine was tested for and found devoid of anorectic activity.
Heterocyclic compounds from 3,3‐dimercapto‐1‐aryl‐2‐propen‐1‐ones. Note 1. 4‐Ary1‐1,3‐dihydro‐2H‐1,5‐benzodiazepine‐2‐thiones
Authors: Nardi D. , Tajana A. , Rossi S.
Published: March 2009

A series of new 4‐aryl‐1,3‐dihydro‐2H‐1,5‐benzodiazepine‐2‐thiones (3) has been synthesized by condensing the 3,3‐dimercapto‐1‐aryl‐2‐propen‐1‐ones with o‐phenylenediamine. The structure was established by the results of acid cleavage and by nmr spectra. The alkylation of compounds 3 gave 2‐alkylthio‐4‐aryl‐3H‐1,5 benzodiazepines (10).
Heterocyclic studies: New heterocyclic ring systems from isomeric dimethyl diaminophthalates
Authors: Williams R. L. , Shalaby S. W.
Published: March 2009

The synthesis and reactions of dimethyl 3, 4‐ and 4, 5‐diaminophthalate 7 and 9 were investigated. The condensation of these isomeric diaminophthalates and their respective nitroacetamido precursors have been shown to give rise to a variety of five, six and seven membered heterocyclic ring system. Several new tetraazanthracenes have also been prepared in this sequence.
Reactions of 1,2‐Dimethyl‐5‐nitroimidazole, novel methods of conversion of the 2‐Methyl group to a nitrile
Authors: Albright J. Donald , Shepherd Robert G.
Published: March 2009

1, 2‐Dimethyl‐5‐nitroimidazole(1)and N,N‐dimethylformamide dicyclohexylacetal gave the 2‐(β‐dimethylaminovinyl) analog 2 and with iodine and pyridine gave the 2‐(1‐pyridinium)methyl compound 3. Benzoyl chloride‐triethylamine and 1 led to benzoylation of the 2‐methyl group to give ketone 9 as the enol benzoate. Nitrous acid or nitrosylsulfuric acid with 9 or its enol ester afforded the oximinoketone 10 which was cleaved with thionyl chloride to give 2‐cyano‐1‐methyl‐5‐nitroimidazole (11) in high overall yield. 1‐Ethyl‐2‐methylbenzimidazole (22) was converted to 2‐cyano‐1‐ethylbenzimidazole (25) similarly. Reaction of 1 with ethyl oxalyl chloride and triethylamine afforded ethyl 1‐methyl‐5‐nitro‐2‐imidazolepyruvate (19) as the enol oxalate. Nitrous acid and 19 gave the oximino pyruvate 20 which effervesced on mild heating to give 2‐cyano‐1‐methyl‐5‐nitroimidazole (11). The preparation of 1‐methyl‐5‐nitro‐2‐imidazoleacetonitrile (39) is reported.
Minor prodiginine pigments from actinomadura madurae and actinomadura pelletieri
Authors: Gerber Nancy N.
Published: March 2009

Five minor prodiginine pigments were isolated from Actinomadura madurae and A. pelletieri fermentations. Two of the pigments were shown to be methylcyclooctylprodiginine (7) and ethylcyclononylprodiginine (8). For the others, structures containing oxygen functions in the aliphatic chains (11, 12 and 13) were suggested.
Antituberculous compounds. XXVIII. Synthesis of pyrazolopyridines
Authors: Sekikawa Isao , Nishie Jan , Tono‐Oka Shuichi , Tanaka Yorie , Kakimoto Shichiro
Published: March 2009

In a previous paper it was reported that N′‐alkyl derivative of isonicotinic acid hydrazide (INH) was more active against tuberele bacilli than the acyl derivative containing the same number of carbon atoms. The authors subsequently reported that the pyrido[2, 3‐d]pyridazine was closely related to the acyl derivative of INH except that the terminal carbonyl group was cyclized to the pyridine nucleus, therefore these derivatives were not effective against tubercle bacilli; however, pyridopyridazine, which is similar to the alkyl derivatives of INH, will be more effective against tubercle bacilli. According to the similar expectation, some pyrazolopyridines were prepared.
Interconversion of 3‐Acylaminobenzisoxazoles and 3‐(2‐Hydroxyphenyl)‐1,2,4‐oxadiazoles
Authors: Harsányi Kálmán
Published: March 2009

Interconversion of 3‐(2‐hydroxyphenyl)‐1,2,4‐oxadiazoles (1) and 3‐acylaminobenzisoxazoles (2) was observed in the presence of base carboxylate anion, triethylamine, alkali hydroxide, alcoholate. With proton transferring reagents (carboxylate, triethylamine) the equilibrium 1⇌2 is dependent on the substituent R; with anionic reagents (hydroxy anion, ethoxyl anion) the less basic anion of 1 is preferred. Alcohol effects further transformation of this anion and the alcohol adduct anion (6) is subject both to hydrolysis and alcoholysis (7) to yield 3‐amino‐benzisoxazole (3).
Benzo[b]thiophene derivatives. XXI. On the proof of structure of the sulfur isostere of psilocin
Authors: Campaigne E. , Rogers R. B.
Published: March 2009

Differences in the characteristics of several common compounds reported in two independent syntheses of the sulfur analog of psilocin required re‐examination of our products. Additional evidence supporting the structures previously reported by us is presented. This includes proof of 3‐substitution in 4‐methoxy‐3‐β‐dimethylaminoethylbenzo[b]thiophene by deuterium exchange of the 2‐proton, demonstration that the intermediate 4‐methoxy‐N, N‐dimethyl‐3‐benzo[b]thienylglyoxamide is different from the 2‐isomer, and confirmation of the structure of 4‐methoxy‐3‐methylhenzo[b]thiophene, an intermediate in one of the reported syntheses, by three different synthetic methods.
Chemistry of isoindolines. The synthesis of 1,2,3,5,6,7‐Hexahydrobenzo[1,2‐c: 4,5‐c′]dipyrrole and 1,2,3,4,5,6‐Hexahydrobenzo[1,2‐c: 3,4‐c′]dipyrrole
Authors: Slapler John T. , Bornstein Joseph
Published: March 2009

The preparation and properties of 1,2,3,5,6,7‐hexahydrobenzo[1,2‐c: 4,5‐c′]dipyrrole (I) and its isomer, 1,2,3,4,5,6‐hexahydrobenzo[1,2‐c:3,4‐c′]dipyrrole (II), are described. Contrary to the claims of earlier investigators, compound I and its 2,6‐diacetyl and 2,6‐dicarboxarnide derivatives VI and IX are easily preparable, readily isolable, stable substances.
Syntheses and properties of 4,6‐dimelhyl[1,2,5]oxadiazolo[3,4‐d]pyrimidine‐5,7(4H,6H)dione 1‐oxide
Authors: Yoneda Fumio , Sakuma Yoshiharu
Published: March 2009

New convenient syntheses of 4,6‐dimethyl[1,2,5]oxadiazolo[3,4‐d]pyrimidine‐5,7(4H,6H)‐dione 1‐oxide (I) from 1,3‐dimethyl‐6‐hydroxylaminouracil by means of nitrosative and nitrative cyclizations are described. Compound I was converted into 4,6‐dimethyl[1,2,5]oxadiazolo[3,4‐d]pyrimidine‐5,7(4H,6H)dione [4,6‐dimethyl‐5,7(4H,6H)furazano[3,4‐d]pyrimidinedione] by refluxing in dimethylformamide. Transformation of I to 1,3,7,9‐tetramethyl‐2,4,6,8(1H,3H,7H,9H)pyrimido[5,4‐g]pteridinetetrone and/or 1,3,6,8‐tetramethyl‐2,4,7,9(1H,3H,6H,8H)pyrimido[4,5‐g]pteridinetetrone is described.
Studies on the syntheses of analgesics. Part XXXIX . Synthesis of 1,2,3,4,5,6‐ Hexahydro‐8‐hydroxy ‐2,6‐methane‐3,6,1 1‐trimethyl‐2,3‐benzo|g| diazocine and 1,2,3,4,5,10,11,12‐Octahydro‐7‐hydroxy‐1,5‐dimethylpyridazino|2,3‐b| isoquinoline |studies on the syntheses of heterocyclic compounds. Part LXI |
Authors: Kametani Tetsuji , Kigasawa Kazuo , Hiiragi Mincharu , Wakisaka Kikuo , Wagatsuma Nagatoshi , Kusama Osamu , Urya Tsunco
Published: March 2009

1,2,3,4,5,6‐Hexahydro‐8‐hydroxy‐2,6‐methano‐3,6,1 1‐trimethyl‐2,3‐benzo |g| diazocine (IV) and 1,2,3,4,5,10,11,12‐octahydro‐7‐hydroxy‐1,5‐dimethylpyridazino |2,3‐b| isoquinoline (VI) were synthesized from a common intermediate, 3‐(3‐methoxyphenyl)‐2‐butanone (VII), through several steps. Reaction of VII with ethyl bromoacetate gave the mixture of ethyl 4‐keto‐3‐(3‐methoxyphenyl)‐3‐methylpentanoate (XIV) and ethyl 4‐keto‐5‐(3‐methoxyphenyl)hexanoate (XV) which were hydrolyzed and condensed with methylhydrazine to give the 4,5‐dihydro‐5‐(3‐methoxyphenyl)‐2,5,6‐trimethyl‐ (XVIII) and 4,5‐dihydro‐6‐(3‐methoxy‐α‐methylbenzyl)‐2‐methylpyridazine‐3(2H)one (XIX). Reduction of XVIII and XIX followed hy cyclization afforded the 2,3‐benzo |g| diazocine (XXII) and the pyridazino |2,3‐b| isoquinoline (XXIII) which on treatment with 47% hydrobromine acid afforded the phenolic bases (IV and VI), respectively. The mass spectrum of IV, VI, XXII and XXIII was also discussed.
Synthèse de l'oxo‐7 7H cyclohepta[b] pyridine et de quelques dérivés
Authors: Letouzé MM. D. , Duflos J. , Queguiner G. , Pastour P.
Published: March 2009

This communication describes the synthesis of 7‐one (7H) cyclohepta[b]pyridine and some derivatives (6,8‐dimethyl; 8‐methyl; 8‐ethyl….). These compounds have been obtained by condensation of ketones with 2,3‐diformylpyridine.
Synthèse du mèthyl‐1 diformyl‐2,3 pyrrole, de la méthyl‐1 pyrrolo[2,3‐d] pyridazine et de la méthyl‐1 oxo‐6 (6h)cycloheptatrieno[b] pyrrole
Authors: Duflos MM. J. , Letouzé D. , Queguiner G. , Pastour P.
Published: March 2009

This communication describes the synthesis of l‐methyl‐2,3‐diformylpyrrole. This new compound is used to prepare a new heterocycle, l‐methylcyclohepta[b]pyrrol‐6‐one and thus allows a new synthesis of l‐methylpyrrolo[2,3‐d]pyridazine.
Thermal reaction of ethynylphthalimides and hydration of N‐(4‐ethynylphenyl)phthalimide
Authors: Hergenrother P. M.
Published: March 2009

Three ethynyl substituted phenylphthalimides were prepared and characterized by high pressure liquid chromatography, differential scanning calorimetry, and mass spectroscopy. When the preparation of N‐(4‐ethynylphenyl)phthalimide was attempted by the thermal cyclodehydration of N‐(4‐ethynylphenyl)‐2‐carboxybenzamide, N‐(4‐acetylphenyl)phthalimide was obtained as the major component. This unusual hydration of an ethynyl group was investigated and a mechanism was proposed to explain it.