bluuebunny/crossref_metadata_2025_split huggingface dataset:
Azomethines with electron withdrawing substituents II. 1,4‐Cycloaddition of sulfonyl or acyl isonitrosomalono compounds with cyclopentadiene
Authors: Biehler Jean‐Marie , Fleury Jean‐Pierre 
Published: March 2009

AbstractLe caractère diénophile dcs dérivés isonitrosomaloniques sulfonylés ou acylés dépend étroite‐ment des substituants du carbone (‐CN, ‐COOR, ‐CONH2) et de l'azote (‐O‐SO2‐R, ‐O‐CO‐R) azométhiniques. Les azométhines à substituants nitrile et sulfonyloxy présentent l'activité diénophile la plus marquée. La structure des adduits aza‐2 norbornènes obtenus avec le cyclopentadiène a été déterminée par spectrométrie de R.M.N. La cycloaddition est stéréo‐sélective; les facteurs intervenant dans la transition sont discutés. Selon leur substitution en position 2 ou 3 les aza‐2 norbornenes subissent une scission rétrodienique plus ou moins aisée.
Ring closures from enecarbamoyl thiocyanates. Syntheses of 5,6,7,8‐tetrahydro‐4‐thio‐2,4(lH,3H)‐quinazolinediones and related compounds
Authors: Chupp John P. 
Published: March 2009

AbstractAlkyl (1‐cyclohexen‐1‐yl)carbamoyl chlorides (1) react with thiocyanate ion to form enecarbamoyl thiocyanates (2). In pyridine solution 2 readily isomerizes to the isothiocyanate 4, which however is not isolated, but immediately transformed in good yields to tetrahydro‐4‐thio‐2,4(lH,3H)quinazolinediones (3). Various transformations of 3, including conversion to tetra‐hydro‐2,4(2H,4H)quinazolinedione (5), dithione (6), alkylation products (8 and 9), sodium salts 11 and Raney nickel degradation to 4,4a,5,6,7,8,8a‐octahydro‐l‐methyl‐2(1H)quinazolinone (7), were carried out to investigate their chemistry and substantiate structural assignments.
Isothiazolcs III: 2‐carbamoyl‐4‐isothiazolin‐3‐ones
Authors: Lewis Sheldon N. , Miller George A. , Szamborski Eugene C. , Hausman M. 
Published: March 2009

AbstractThe reaction of several 3‐hydroxyisothiazoles with alkyl and aryl isocyanates has given high yields of 2‐earbamoyl‐4‐isothiazolin‐3‐ones as the only isolahle products. Reaction with an iso‐thioeyanate, however, afforded a mixture of the isomerie 2‐thioearbamoyl‐4‐isothiazolin‐3‐one and 3‐isothiazolyl thiocarbamate.
1,3,5‐Trisubstituted hexahydrotriazines as mannich reagents. II. Preparation of p‐secondary aminomethylphenols
Authors: Reynolds Delbert D. , Cossar Bernard C. 
Published: March 2009

AbstractPhenol and a variety of substituted phenols have been aminomethylated by new Mannich reagents prepared from 1,3,5‐trisubstituted hexahydrotriazines. In contrast to the conventional aminomethylating agents, which react preferentially in the ortho position, the new reagents favor para substitution. A variety of newpara secondary aminomethylphenols have been prepared.
The crystal structure of 2‐hydroxymethylpyridine N‐oxide
Authors: Desiderata R. , Terry J. C. 
Published: March 2009

AbstractThe structure of 2‐hydroxymethylpyridine N‐oxide was determined from X‐ray diffractometer data by a direct method. The compound crystallizes in the monoclinic space group P21/c with cell dimensions a = 7.079, b = 8.046, c = 10.599 Å, cosβ = −0.2252. A total of 1241 independent reflections were refined to an R value of 0.06. The N‐O dative bond has a length of 1.321 Å and the dative oxygen is bonded to a hydroxyl group on a symmetry related molecule by an inter‐molecular hydrogen bond. The structure corroborates recent findings concerning the relationship between the strength of hydrogen bonding to a dative oxygen and the length of the NO dative bond.
Studies on the synthesis of anthyridine
Authors: Carboni S. , Da Settimo A. , Hertini D. , Mori C. , Tonetti I. 
Published: March 2009

AbstractThe sulfuration of various anthyridones (I) to the corresponding thioderivatives (II) and the desulfuration of these to 5,10‐dihydroanthyridine (III) is descrihed. The preparation of anthyridin‐5‐one (1d) from 6 ‐methyl‐2,2 ‐dipyridylamino‐3‐carboxylic acid (V) is also described.
The preparation of 3‐chlorobenzo[b] thiophene derivatives from cinnamie acids
Authors: Wright W. B. , Brabander H. J. 
Published: March 2009

AbstractThe reaction of cinnamic acid derivatives with thionyl chloride and pyridine is a general procedure for the preparation of derivatives of 3‐chlorobenzo[b] thiophene‐2‐carbonyl chloride from readily accessible starting materials. These compounds are easily converted to the corresponding acids, esters and amines.
7‐Deazapurines II. Syntheses and reactions of 5‐aminopyrrolo[2,3‐d] pyrimidine‐6‐carbonitrile and related compounds
Authors: Kim Dong Han , Santilli Arthur A. 
Published: March 2009

AbstractThe reaction of 4‐chloro‐2‐phenyl‐5‐pyrimidinecarbonitrile (III) with N‐methylglycinonitrile gave 4‐[(eyanomethyl)methylamino]‐2‐phenyl‐5‐pyrimidinecarbonitrile (VIa), which upon cycli‐zation under Dieckmann conditions afforded 5‐amino‐7‐methyl‐2‐phenyl‐7H‐pyrrolo[2,3‐d]‐pyrimidine‐6‐carbonitrile (VIIa). Other examples (VIIb and VIIc) were prepared similarly from the reactions of III with glycinamide and ethyl glycinate, respectively. The preparation of simple 5‐amino derivatives of the pyrrolo[2,3‐d] pyrimidines thus synthesized is described. The alkyla‐tion of VIIc with N‐cyeloheptylchloroacetamide took place at the ring nitrogen, giving XII. The reaction of VIIa with formamide gave 4‐amino‐5‐methyl‐7‐phenyl‐5H‐pyrrolo[2,3‐d:4,5‐d′ ]‐dipyrimidine (XIII), the first member of a new ring system. Treatment of VIIa with carbon disulfide and pyridine afforded another example of this new ring system, 1,5‐dihydro‐5‐methyl‐7‐phenyl‐2H‐pyrrolo[2,3‐d:4,5‐d′] dipyrimidine‐2,4‐(3H)dithione (XIV).
Nitrene insertion reactions. Part III. The steric effect of the Isopropyl and t‐butyl groups. 1,6 Type cycloaddition of tetracyanoethylene to 1H‐azepines
Authors: Photis James M. 
Published: March 2009

AbstractVarious alkyl and aryl carboxynitrenes generated thermally from the azidoformates react with para‐di‐t‐butylbenzene with a high degree of selectivity to yield predominantly, or exclusively, 3,6‐di‐t‐butylazepine‐N‐carboxylates. 3,6‐Dialkylazepines react readily with tetracyanoethylene to afford the first known TCNR‐1H‐azepine cycloadducts of the 1,6 type.
Synthesis of furo[2,3‐b]pyridine
Authors: Mcfarland J. W. , Wollerman R. P. , Sadler W. C. , Coleman G. N. 
Published: March 2009

AbstractTwo routes were employed to synthesize unsubstituted furo[2,3‐b]pyridine (IV). The first method started with ethyl 5‐aminofuro[2,3‐b] pyridine‐2‐carboxylate (1) and involved successive deamination, hydrolysis, and decarboxylation. The second method began with 5‐nitrofuro[2,3‐b ]‐pyridine‐2‐carboxylic acid (V) and consisted of successive decarboxylation, reduction, and deamination reactions.
2,2′‐Disubstituted 5,5′‐bipyrimidines
Authors: Pater Richard 
Published: March 2009

AbstractSyntheses of 2,2′‐bis(methylthio)‐, 2,2′‐diamino‐, 2,2′‐dihydroxy‐, 2,2′ ‐dichloro‐, and 2,2′ ‐diethoxy‐5,5;′‐bipyrimidines are described.
Syntheses of benzomorphan and related compounds. Part III. An alternate synthesis of 3‐substituted‐1,2,3,4,5,6‐hexahydro‐8‐hydroxy‐2,6‐methano‐6,11‐dimethyl‐3‐benzazocine
Authors: Kametani T. , Kigasawa K. , Hayasaka M. , Wakisaka K. , Satoh F. , Aoyama T. , Ishimaru H. 
Published: March 2009

AbstractReduction of the appropriate Schiff bases gave 5‐benzylamino‐3‐methyl‐2‐pentene (XVII) and l‐benzylamino‐3‐methylpentane (XVIII), the condensation of which with methyl 3‐(4‐methoxyphenyl)‐2,3‐epoxypropionate afforded a mixture of the isomeric 1‐benzyl‐2‐(4‐methoxy‐benzyl)‐3,4‐dimethyl‐4‐hydroxypiperidines (XIXa and XIXb). The piperidinols were heated with hydrobromic acid, respectively, to afford 3‐benzyl‐1,2,3,4,5,6‐hexahydro‐8‐hydroxy‐2,6‐methano‐6,11‐dimethyl‐3‐benzazocine (II). Since the conversion of II to pentazocine (Ic) had already been accomplished, an alternate synthesis of Ic was achieved.
Mass spectra of some 1,2,4‐triazole derivatives
Authors: Potts K. T. , Armbruster R. , Houghton E. 
Published: March 2009

AbstractFragmentation of various 1,2,4‐triazole derivatives occurs by two predominant pathways involving the loss of RCN originating from both C3 and C5 positions. The resulting diazirinium radical cation was observed to lose a nitrogen atom to give a nitrilium ion whose substitution pattern was dependent upon the original substituents in the nucleus.
The synthesis of some 7‐ and 7,8‐substituted 2,3,4,5‐tetrahydro‐1H‐3‐benzazepines
Authors: Pecherer B. , Sunbury R. C. , Brossi A. 
Published: March 2009

AbstractThe nitration of 2,3,4,5‐tetrahydro‐1H‐3‐benzazepine and its 3‐methyl and 3‐acetyl derivatives yields the corresponding 7‐nitro derivatives which can be further transformed by classical procedures. The preparation of the ether cleavage products of the known 2,3,4,5‐tetrahydro‐7,8‐dimethoxy‐1H‐3‐benzazepine is also reported.
Synthesis of two new heterocyclic ring systems: Benzo[3,4] cyclohepta[1,2‐d]‐pyrimidines and benzo[3,4]cyclohepta[2,1‐d] pyrimidines
Authors: Rosowsky Andre , Chen Katherine K. N. , Lin May , Nadel Marilyn E. , Amand Richard St. , Yeager Sandra A. 
Published: March 2009

AbstractThree 2,4‐diamino‐l(), 11‐dihydro‐9H‐benzo[3,4]cyclohepta[ 1,2‐d]pyrimidines (6a‐6c) representing the first examples of a new ring system were synthesized from 2‐benzosuberones and cyanoguanidine. Similarly, 2,4‐diamino‐6,7‐dihydro‐5H‐benzo[3,4]cyelohepta[2,1‐d]pyrimidine (24) was prepared from 1‐benzosuberone. The ultraviolet spectral properties of these compounds were examined with reference to those of the analogs in which the central ring is five‐ and six‐mernbered.
Reactions of some pyranylidene esters with amines
Authors: Van Allan J. A. , Reynolds G. A. 
Published: March 2009

AbstractThe reactions of 4‐(2,2‐dimethyl‐4,6‐dioxo‐1,3‐dioxan‐5‐ylidene)‐2,6‐diphenyl‐4H‐pyran (1) with primary amines gave the corresponding 1‐substituted 1,4‐dihydropyridine derivatives. The related benzo derivative of 1 (12) and primary amines gave 3‐substituted 3,4‐dihydro‐2‐phenyl‐5H‐[1]benzopyrano[3,4‐c] pyridine‐4,5‐dione derivatives. With secondary amines, 12 gave 2‐phenyl‐4H,5H‐pyrano[3,4‐c] [1]benzopyrane‐4,5‐dione, and with isopropylamine, N,N‐dimethylhydra‐zine, and methanolic potassium hydroxide, 12 gave 4‐phenacylcoumarin. Some reaction intermediates were isolated which indicate probable reaction paths. The reactions with amines were extended to a naphtho derivative of 1 (19) and to a thia homolog of 12 (24).
Synthesis of amino‐5‐arylsulfonylpyrimidines
Authors: Santilli Arthur A. , Rosenberg Murray D. , Osdene T. S. , Childress Scott J. 
Published: March 2009

AbstractSeveral new 4‐amino‐5‐arylsulfonylpyrimidines were prepared via the reaction of various α‐(ethoxymethylene)arylsulfonylacetonitriles with guanidine or variously substituted amidines (Table II). 2,4‐Diamino‐5‐(p‐chlorophenylsulfonyl)pyrimidine (IIIg), a typical example, was prepared from the reaction of 2‐(p‐chlorophenylsulfonyl)‐3‐ethoxyacrylonitrile (IId) with guanidine in refluxing ethanol containing sodium ethoxide. With proper substitution of the ethoxymethylene intermediate, the method was found suitable for the preparation of other compounds having either a hydroxy or methyl group at the 4‐position of the 5‐arylsulfonylpyrimidine. The fluoro group in 2,4‐diamino‐5‐(p‐fluorophenylsulfonyl)pyrimidine (IIIx) was successfully replaced by nucleophilic reagents such as sodium ethoxide, N‐methylpiperazine and N,N‐diethylethylene‐diamine. Attempts at direct displacement of fluorine by ammonia at 190° were unsuccessful.
Enol‐keto tautomerism of alkyl 2‐picolyl ketones
Authors: Wursthorn Karl R. , Sund Eldon H. 
Published: March 2009

AbstractAn analysis of the ir and nmr spectra taken on a series of nine different alkyl 2‐picolyl ketones clearly indicates that there is an enol‐keto tautomerism. The enol:keto ratio exhibits a marked dependence on both solvent polarity and the nature of the alkyl group. The equilibrium values correlate with the Taft sleric substituent constants.
Organosilicon compounds XV. Cleavage of the silicon‐carbon bond of 2‐trimethylsilyl‐1‐methylimidazole and 2‐trimethylsilyl‐1‐methylbenzimidazole
Authors: Pinkerton Frank H. , Thames Shelby F. 
Published: March 2009

AbstractCleavage of the aryl‐silicon bond of 2‐trimethylsilyl‐1‐methylimidazole (Ia) and 2‐trimethylsilyl‐1‐methylbenzimidazole (Ib) has been effected by five carbonyl reagents, i.e. aldehydes, acid halides, chloroformates, anhydrides and isocyanates, to provide a novel synthetic route to a host of functionally substituted heterocycles. Compound Ia reacted exothermically at room temperature, with four of the, five carbonyl reagents.
Pyrimidine N‐oxides. Preparation of 6‐chloro‐2,4‐diaminopyrimidine 3‐N‐oxide and its reactions
Authors: Delia Thomas J. , Venton Duane L. 
Published: March 2009

AbstractThe peroxyacid oxidation of 6‐chloro‐2,4‐diaminopyrimidine (1) led to two products, 6‐chloro‐2,4‐diaminopyrimidine 3‐N‐oxide (2) and 2,4‐diamino‐5,6‐dichloropyrimidine 3‐N‐oxide (3). The assignment of structure of both of these compounds was made on the basis of ir, uv, nmr, and mass spectral data. A discussion of the pathways involved in the formation of 3 is presented.
On the mechanism of the 1,2‐cycloaddition reaction of ketenimines and nitrosoarenes
Authors: Barker Marvin W. , Combs Leon L. , Gill Jack T. 
Published: March 2009

AbstractThe 1,2‐cycloaddition of nitrosoarenes to ketenimines producing 3‐iminosubstituted‐1,2‐oxazetidines has been found to proceed more rapidly if photosensitized conditions are employed. This data plus the specificity of the reaction allows for a reasonable postulation of the non‐photochemical room temperature reaction.
Cycloaddition reactions of some analogs of the acridizinium ion
Authors: Bradsher C. K. , Frazer M. G. , Burnham W. S. 
Published: March 2009

AbstractThe 1‐aryl‐2‐imidazo[1,2‐b]isoquinolin‐4‐ium system (3 and 4), prepared by the action of aniline, or a suitable aniline derivative upon 2‐phenacyl‐3‐chloroisoquinolinium bromide undergoes cycloaddition reactions only with the more nucleophilic alkenes such as cyclopentadiene or 9‐vinylcarbazole.The pyrazino[1,2‐b]isoquinolin‐5‐ium‐2‐oxide (8–10) system reacts with nucleophilic alkenes more readily than does the acridizinium system 1. For both systems the cycloaddition appears to occur across the meso position of the central ring.
Mass spectrometric investigation of isomeric 1,2,3,4‐tetrahydro‐4‐oxoquinazolines
Authors: Bogentoft Conny , Danielsson Bengt 
Published: March 2009

AbstractSix isomeric methylphenyl‐1,2,3,4‐tetrahydro‐4‐oxoquinazolines have been prepared and their fragmentation patterns upon electron impact studied. Deuterium labelling and high‐resolution measurements were performed in order to facilitate the interpretation of the spectra. The dissociation of the molecular ion follows two main routes, the fragmentation being governed by the position of the phenyl group.
Fluorescence and liquid scintillation properties of 1,3,4‐oxadiazoles. I. Excimer formation in 2‐alkyl‐5‐(4‐biphenylyl)‐1,3,4‐oxadiazoles
Authors: Taber Richard L. , Binkley Edward S. 
Published: March 2009

AbstractSeveral 2‐alkyl‐5‐(4‐biphenylyl)‐1,3,4‐oxadiazoles have been synthesized and investigated as primary liquid scintillation solutes and are found to be excellent fluors. Fluorescence studies at varying concentrations and temperatures indicate that excimer formation is possible at high concentration and low temperatures.
Mesoionic compounds VIII. Synthesis of 3‐phenylsydnonyl substituted alkenes. Some new photochromic sydnones
Authors: Greco Claude V. , O'Reilly Bernard P. 
Published: March 2009

AbstractThe reactions of 3‐phenylsydnonyllithium with a variety of ketones to afford tertiary carbinols 4a‐4i and their subsequent dehydration to 4‐(3‐phenylsydnonyl) alkenes 5a‐5i are discussed. Among the alkenes, 2‐[4‐(3‐phenylsydnonyl)]propene (5b) and 1‐[4‐(3‐phenylsydnonyl)]‐1‐cyclohexene (5i) were photochromic. A Wittig reaction between ethyl‐4‐(3‐phenylsydnonyl)‐ketone and methylenetriphenylphosphorane afforded the photochromic 2‐[4‐(3‐phenylsydnon‐yl)]‐1‐butene(5j).
O‐ and N‐substituted products from the treatment of 3,5‐dichioro‐2‐pyridone with benzenesulfonyl chlorides
Authors: Hamer Martin , Lira E. Patrick 
Published: March 2009

AbstractTreatment of 3,5‐dichloro‐2‐pyridone with various benzenesulfonyl chlorides in the presence of triethylamine at 25° yielded both O‐ and N‐sulfonylated products. These isomers were isolable, relatively stable compounds which were distinguished by their ir and uv spectra.
2,1‐benzisothiazoline 2,2‐dioxide. I. Some 3‐substituted derivatives
Authors: Skorcz Joseph A. , Suh John T. 
Published: March 2009

AbstractA number of 3‐mono‐ and 3,3‐disubstituted derivatives of 1‐methyl 2,1‐benzisothiazoline 2,2‐dioxide (IIa), a unique benzosultam, were synthesized. Starting materials for the condensation and aminoalkylation reactions utilized were IIa and the 3‐methyl compound IIb, which were prepared by cyclization of the 2′‐chloro‐N‐methylalkylsulfonanilides, Ia and b, respectively.
The preparation of 3,5‐disubstituted tetrahydro‐4H‐1,3,5‐oxadiazine‐4‐thiones, tetrahydro‐4H‐1,3,5‐thiadiazin‐4‐ones, and tetrahydro‐4H‐1,3,5‐thiadiazine‐4‐thiones
Authors: Seidel Michael C. , Boettner Fred E. 
Published: March 2009

AbstractThe reaction of 1,3‐disubstituted thioureas with formaldehyde under acidic conditions with removal of water yielded 3,5‐disubstituted tetrahydro‐4H‐1,3,5‐oxadiazine‐4‐thiones. When hydrogen sulfide was bubbled through the reaction mixture, the corresponding tetrahydro‐4H‐1,3,5‐thiadiazine‐4‐thiones were formed. Similarly, starting from 1,3‐disubstituted ureas, a number of tetrahydro‐4H‐1,3,5‐thiadiazine‐4‐ones were prepared. The latter compounds were also oxidized to the corresponding sulfoxides and sulfones.
1H‐pyrazolo[3,4‐b]pyridines
Authors: Höhn H. , Denzel Th. , Janssen W. 
Published: March 2009

AbstractThe synthesis of a number of new 1H‐pyrazolo[3,4‐b]pyridine‐5‐carboxylic acid derivatives is described. Most of these compounds have either an alkoxy or a basic substituent in position 4.
Quinazolines. VII. Synthesis of 1,3‐Diamino‐5,6‐dihydrobenzo[f]quinazolines
Authors: Rosowsky Andre , Chen Katherine K. N. , Papathanasopoulos Nickolas , Modest Edward J. 
Published: March 2009

AbstractEighteen new 1,3‐diamino‐5,6‐dihydrobenzo[f] quinazolines (6, R. = alkyl, Cl, MeO) were synthesized via the condensation of appropriate 2‐tetralones with cyanoguanidine under fusion conditions. Methods were developed for the preparation of a number of heretofore undescribed 2‐tetralones as precursors. The final products can be viewed as conformationally rigid analogs of pyrimethamine (2), and are of interest as inhibitors of dihydrofolate reductase and as potential antimalarial and antitumor agents.
Quinazolines. VIII. Synthesis of 1,3‐diaminobenzo[f]quinazolines
Authors: Rosowsky Andre , Chen Katherine K. N. , Nadel Marilyn E. , Papathanasopoulos Nicholas , Modest Edward J. 
Published: March 2009

AbstractTwenty‐one 1,3‐diaminobenzo[f]quinazolines (2, R = H, alkyl, halogen, methoxy) were synthesized as planar tricyclic analogs of the antimalarial agent pyrimethamine (1). The synthetic methods included i) condensation of 1‐cyano‐2‐naphthylamines with cyanamide in the presence of pyridine hydrochloride, ii) cyclization of N1,N5‐bis(2‐naphthyl)biguanide hydrochlorides in diphenyl ether at 250°, iii) reaction of 2‐naphthylamine hydrochlorides with excess sodium dicyanamide in boiling 1‐octanol, and iv) selenium dioxide dehydrogenation of 1,3‐diamino‐5,6‐dihydrobenzo[f]quinazolines. A number of new 2‐naphthols and 2‐naphthylamines were synthesized as intermediates. Substituent effects on the ultraviolet absorption spectra of 1,3‐diamino‐benzo[f]quinazolines were investigated and found to be additive. These compounds are of interest as inhibitors of dihydrofolate reductase and as potential antimalarial and antitumor agents.
Tautomerism of 2‐amino‐2‐oxazolin‐4‐ones. II
Authors: Rapi G. , Ginanneschi M. , Belgodere E. , Chelli M. 
Published: March 2009

AbstractThe study of the tautomerism of 2‐amino‐2‐oxazolin‐4‐one (1) and its methyl derivatives has been completed. The methylation of 1 gave 2‐imino‐3‐methyloxazolidin‐4‐one (4) and 2‐methyl‐amino‐2‐oxazolin‐4‐one (7). All attempts to isolate O‐methyl derivatives failed. The uv, nmr, ir, and Raman spectra led to the definite conclusion, in agreement with the chemical evidence, that the 2‐aminooxazolinic form a, if it is theoretically possible, predominates in all compounds investigated. Otherwise the 2‐iminooxazolidinic form b predominates. The assignment of the carbonyl stretching is discussed on the basis of ir and Raman data. The nmr spectrum of compound 7 shows anomalous behaviour, most probably due to the existence of a monomer‐dimer equilibrium.
Synthesis of pyrimido[4,5‐e][1,4]oxazepin‐5‐ones
Authors: Santilli Arthur A. , Kim Dong Han , Wanser Stephen V. 
Published: March 2009

AbstractEighteen 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

AbstractAn 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

AbstractThe 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

Abstract7,8‐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

Abstract7‐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.