bluuebunny/crossref_metadata_2025 huggingface dataset:
Fluorinated nitrogen heterocycles via cyclization. III. 3‐trifluoromethyl‐1‐(4‐trifluoromethyl‐2‐pyridyl)‐pyrazoles from fluorinated 1,3‐diketones and 4‐trifluoromethyl‐2‐hydrazinopyridines
Authors: Pitman‐Dunn Seymour Portnoy
Published: March 2009

Fluorinated 1,3‐diketone compounds having the general structure CF3COCH2COR1 underwent cyclization with 4‐trifluoromethyl‐2‐hydrazinopyridines (IV) to give a series of 3‐trifluoro‐methyl‐1‐(4‐trifluoromethyl‐2‐pyridyl)‐pyrazoles (V). The hydrazinopyridine intermediates (IV) were prepared by conversion of 4‐trifluoromethyl‐2‐pyridones (II) to the chloropyridines (III) followed by treatment of the latter with hydrazine hydrate.
Analogues non glycosidiques des nucléaosides. III. (Méthylène téatrahydro‐2′ furyl)‐1 uracile, thymine et cytosine. (méathylégne téatrahydro‐2′‐r furyl)‐1 uracile
Authors: Defaye J. , Naumberg M. , Reyners T.
Published: March 2009

Dans le cadre de travaux ayant pour objectif la modification de la réactivité de la liaison base‐sucre des nucléosides et analogues, les dérivés substitués de l'uracile, de la thymine et de la cytosine par les radicaux méthylène tétrahydro‐2 furyle et tétrahydro‐2‐R furyle ont été préparés. Dans ce but, différentes méthodes d'alkylation des pyrimidines ont été étudiées. La préparation de l'énantiomère de configuration absolue R de I'alcool tétrahydro‐2 furfurylique est décrite.
Acylation of nitrogen heterocycles under the conditions of the schotten‐baumann reaction. III. Imidazoles
Authors: Babad E. , Ben‐Ishai D.
Published: March 2009

Imidazole and five N‐monoalkylimidazoles were tested for their ability to undergo ring fission on carbobenzoxylation. Reaction occurred only with imidazoles substituted with strong electron withdrawing groups such as nitrophenyl, dinitrophenyl and monocarbobenzoxy.
Ring‐opening nucleophilic alkylations by tertiary azetidines
Authors: Gaertner V. R.
Published: March 2009

N‐Alkylazetidines were cleaved by nucleophilic reagents under moderate conditions to give the corresponding 3‐substituted‐propylamines. The additions were subject to acid catalysis and also proceeded slowly under alkaline S conditions.
New microbial phenazines
Authors: Gerber Nancy N.
Published: March 2009

Eleven phenazines were identified as fermentation products of a bacterium. They included the previously unknown 2,9‐dihydroxyphenazine‐1‐carboxyIic acid (4), 1,8‐phenazinediol‐1()‐oxide (5) and 8‐amino‐1‐phenazinol (6) as well as phenazine‐1,6‐dicarboxylic acid (1),9‐hydroxyphena‐zine‐1‐carboxylic acid (2) and 1,8‐phenazinediol (3) not isolated before from natural sources.
On the nitration of 2‐pyrone
Authors: Pirkle W. H. , Dines M.
Published: March 2009

A 1:1 adducl of 2‐pyrone and nitronium fluoroborate has been delected by nmr and is a possible precursor of 5‐nitro‐2‐pyrone, a subsequently formed product. From comparison of the nmr spectra of the 1:1 adduct and 2‐methoxypyrylium fluoroborate, the adduct is believed to be the pyrylium fluoroborate derived from nitration of the carbonyl oxygen of 2‐pyrone.
Thiocarbonyls. X. The Isomeric 2,4,6‐Tris(halophenyl)‐1,3,5‐thianes
Authors: Campaigne E. , Georgiadis M. P.
Published: March 2009

Nine pairs of isomeric 2,4,6‐tris(halophenyl)‐1,3,5‐trithianes have been assayed in the crude state by n.m.r. techniques, and separated and purified by chromatography. Contrary to previous reports, the α‐(cis, trans)‐isomers are the major products in most cases. These compounds are shown to exist as puckered chair trithiane structures, even in the more hindered α‐(cis, trans)‐o‐halophenyl cases, by the clear resolution of axial and equatorial trithiane ring protons in a ratio of 2:1. Ano‐halogen on an axial phenyl group in the α‐isomers causes the aromatic group to exert an anisotropic deshielding effect on adjacent axial protons, so as to cause the axial and equatorial proton peaks to appear as a singlet in some solvents. Melting point differences, in several cases quite large, from those previously reported have been observed for six of the eighteen triaryltrithianes reported.
Products from lactones and hydrazines: Hydroxyalkanohydrazides and pyrazolidones
Authors: Allen C. F. H. , Magder Edna Weismann
Published: March 2009

Saturated aliphatic lactones and dihydrocoumarins have been characterized by the formation of their crystalline 1:1‐adducts (hydroxyalkanohydrazides) with hydrazine hydrate. A new procedure, which involves the use of azeotropic distillation to remove the water present, greatly facilitates the reaction by reducing the time required. Three macrocyclic lactones, that did not react in either of two short procedures, readily formed the same type of 1:1‐adducts after several hours of refluxing of the components in alcoholic solution. The unsaturated macrocyclic lactone gave two products of cleavage; one was the expected ω‐hydroxyalkenohydrazide, but the other was its saturated analog, in which the double bond had been reduced by the excess hydrazine employed. β‐Lactones are a special case, requiring variations in conditions; the yield of the simplest adduct was more than doubled by a new procedure. In one instance products in which the lactone ring had been opened in both possible ways were obtained for the first time. A “stream‐lined extracter” was useful with the low melting adducts. Coumarins themselves gave either 1:2 adducts or pyrazolidones. The latter could also be prepared from the adducts.

A study of 4‐hydroxybutanohydrazide in a mass spectrometer showed that both γ‐butyro‐lactone and 5‐methyl‐3‐pyrazolidone are thermal products. Pure 5‐methyl‐3‐pyrazolidone has now been isolated from the syrupy reaction product of ethyl crotonate and hydrazine, It has been converted to benzylidene derivatives; spectral data of the latter are consistent with their polarized structures.
Benzacridines VI.. Functional derivatives of 5,6‐dimethylbenz[c]acridine
Authors: Cromwell Norman H. , Nielsen Lawrence A.
Published: March 2009

5,5‐Dimethyl‐5,6‐dihydrobenz[c]acridone has been synthesized by three different routes: a, from a condensation of anthranilic acid with 4,4‐dimethyl‐1‐tetraIone; b, by a catalytic hydrogenation of 2‐(o‐nitrobenzal)‐4,4‐dimethyl‐1‐tetralone oxide followed by an acid catalyzed cleavage of the oxide ring and closure of the nitrogen heterocyclic ring; c, a multi‐step process starting with 7‐carboxy‐5,5‐dimethyl‐5,6‐dihydrobenz[c]acridine. Several new functional derivatives of both 5,5‐dimethyl‐5,6‐dihydrobenz[c]acridine and of 5,6‐dimethylbenz[c]acridine were also produced for biological study by others.
Ellipticine analogs: Oxygen and sulfur isosteres
Authors: Fujiwara Allan N. , Acton Edward M. , Goodman Leon
Published: March 2009

Oxaellipticine has been synthesized from 1,4‐dimethyldibenzofuran, by converting it to the 2‐aldehyde, forming the Schiff's base with aminoacetaldehyde diethyl acetal, and cyclizing this with 105%superphosphoric acid. Alternatively, tetrahydrodimethyldibenzofuran was formylated mainly at the 3‐position, and the 3‐(2‐nitrovinyl) derivative of the 3‐aldehyde, by hydride reduction, then Bischler‐Napieralski cyclization of the 3‐(2‐formamidoethyl) derivative, afforded hexahydrooxaellipticine, which could be aromatized only in poor yield. Isooxaellipticine, the pyrido‐A' positional isomer, was similarly prepared from the nitrovinyl derivative of 1,4‐dimethyl‐2‐dibenzofurancarboxaldehyde, through cyclization of the formamidoethyl intermediate and aromatization of the dihydro product. Likewise, isothiaellipticine was obtained from 1,4‐dimethyl‐2‐dibenzothiophenecarboxaldehyde.
The mass spectra of formycin, formycin B and showdomycin carbon linked nucleoside antibiotics
Authors: Townsend Leroy B. , Robins Roland K.
Published: March 2009

The mass spectra of the nucleoside antibiotics formycin (I), formycin B (II) and their heterocyclic aglycons (7‐aminopyrazolo[4,3‐d]pyrimidine and pyrazolo[4,3‐d]‐7‐pyrimidone) have been studied utilizing high resolution mass spectroscopy. The major electron‐impact fragmentation pattern exhibited by the heterocyclic aglycons can be explained by the initial expulsion of hydrogen cyanide followed by decarbonylation or by loss of a second mole of hydrogen cyanide. There is a striking difference in the fragmentation pattern of these nucleoside antibiotics where the glycoside linkage is a C‐C bond as compared to nucleosides possessing a C‐N bond linkage. The base peak observed for formycin and formycin B occurred at B + 30 in direct contrast to the usual nucleosides where the B + 1 or B + 2 normally occurs as the predominant peak. This pattern suggests that such a carbon linked nucleoside should be readily identified by this means. The mass spectrum of showdomycin (3‐β‐D‐ribofuranosylmaleimide, III) was also determined and found to exhibit a similar parent peak at B + 30. This base + 30 peak has been assigned to the aglycon plus a protonated formyl group which results from fragmentation of the sugar. Mass spectrometry should prove very useful in the future structural elucidation of carbon linked nucleoside derivatives since these features (B + 30 and M‐103) may be considered diagnostic.
Perhaloketones XIX . Derivatives of benzo‐N‐heterocycles
Authors: Gilbert Everett E.
Published: March 2009

A study was made of the behavior of imidazole and six benzo‐N‐heterocyclic compounds upon direct treatment with anhydrous and hydrated hexafluoro‐ and sym‐tetrafluorodichloroacetones. Two of the compounds did not react, and four gave addition compounds. Indole reacted with both ketones in the 3‐position. Heterocyclic precursors were made by reacting o‐phenylenediamine, o‐aminophenol, and o‐aminobenzenethiol with hexafluoroacetone hydrate, thus introducing the 2‐hydroxyhexafluoro‐2‐propyl moiety into the ring para to the amino group. A similar product was made from o‐phenylenediamine and tetrafluorodichloroacetone. These compounds were then converted to twenty‐eight heterocyclic derivatives. Four of the latter underwent haloform cleavage of the hydroxyhexahalopropyl group, a novel, but not widely applicable, preparative approach to the corresponding heterocyclic carboxylic acids.
Synthesis and reactions of 4,6‐dimethoxyindole, an unusual indole system
Authors: Brown Vernon H. , Skinner W. A. , Degraw Joseph I.
Published: March 2009

A synthesis of 4,6‐dimethoxyindole is described. Formylation or oxalylation reactions gave substitution at position 7 rather than the usual 3‐substitution characteristic of other indoles. A synthesis of N,N‐dimethyl‐4,6‐dimethoxytryptamine is presented along with NMR data for 3 and 7‐substituted compounds in this series.
Preparation of bis‐pyrylium salts
Authors: Reynolds C. A. , Vanallan J. A.
Published: March 2009

Six methods are described for the preparation of bis‐pyrylium salts: (1) treatment of 4,4′‐bi‐2‐flavene or 4‐(4H‐flav‐2‐en‐4‐yl)flavylium perchlorate with triphenylmethyl perehlorate; (2) reaction of an aromatic o‐hydroxyaldehyde and 1,4‐deacetylbenzene under acidic conditions; (3) reaction of o‐hydroxyacetophenone, 1,4‐diacetylbenzene, perchloric acid and acetic acid; (4) reaction of a 2‐ or 4‐methylpyrylium salt with 2‐ or 4‐pyrone in the presence of phosphorus oxychloride; (5) oxidation of a 1,2‐ethanediylidenebis‐flavene or ‐thiaflavene, a bis‐flavenylidene or ‐thiaflavenylidene, and a bis‐pyranylidene or ‐thiapyranylidene by means of cupric perchlorate; and (6) reaction of 4‐methylflavylium and ‐thiaflavylium perchlorate with bromine in acetic acid.
Alcoholation of the trifluoromethyl group. I. Ortho esters derived from 1‐ and 3‐trifluoromethylphenothiazines
Authors: Saggiomo Andrew J. , Asai Masaru , Schwartz Pauline M.
Published: March 2009

The preparation of 1‐trifluoromethylphenothiazine is reported. Methanolic basic hydrolysis of 1‐ and 3‐trifluoromethylphenothiazines to the corresponding ortho esters of phenothiazine‐carboxylic acids is described.
A study of the synthesis and some reactions of 3‐phenyl‐1,4‐benzothiazines
Authors: Wilhelm Max , Schmidt Paul
Published: March 2009

Condensation of o‐aminothiophenol with 2‐bromoacetophenone yields 3‐phenyI‐1,4‐benzo‐thiazine hydrobromide, which upon treatment with alkali gave a mixture of 3‐phenyl‐2H‐1,4‐benzothiazine (VIIa) and 3‐phenyl‐4H‐1,4‐benzothiazine (VIIb). Catalytic hydrogenation led to rearrangement of the benzothiazine (VIIa) to 2‐phenyl‐2‐methyl‐2,3‐dihydrobenzothiazole (X), while reduction with lithium aluminium hydride resulted in 3‐phenyl‐2,3‐dihydro‐4H‐1,4‐benzothiazine (XVI). The latter was transferred to 3‐phenyl‐4‐aminoalkyl‐2,3‐dihydro‐4H‐1,4‐benzothiazines (XVII and XVIII).
Toxic chlorinated methanoisobenzofuran derivatives
Authors: Weil E. U. , Colson J. G. , Hoch P. E. , Gruber R. H.
Published: March 2009

Upon treatment with alcoholic base, 1,4,5,6,7,7‐hexachloro‐5‐norbornene‐endo‐cis‐2,3‐dimethanol (1) yields a tricyclic ether (111) which is converted by sulfuric acid to two epimeric 4,6,7,8,8‐pentachloro‐octahydro‐4,7‐methanoisobenzofuran‐5‐ones (111 A & B). These relatively nontoxic isomers, upon introduction of two chlorine atoms α and α′ to the ether oxygen, yield two epimeric products of high toxicity to insects and mammals. These 1,3,4,6,7,8,8‐heptachloro‐octahydro‐4,7‐methanoisobenzofuran‐5‐ones (IV A & B) upon transannular dehydrochlorination yield a toxic tetracyclic ketone (VI A). Reduction of this ketone by lithium aluminum hydride affords an alcohol (VII) of similarly high insecticidal toxicity. Nuclear magnetic resonance and infrared spectra are presented as evidence for the indicated structures. Results of this study are interpreted as indicative of the regions of the molecule which are critical in regard to toxicity.
N‐polyfluoroalkyl aziridines
Authors: Thorn K. F. , Sweeny N. P. , Mcbrady J. J.
Published: March 2009

Aziridines add almost quantitatively and without ring opening to tetrafluoroethylene and chlorotrifluoroethylene to yield N‐polyfluoroalkyl aziridines. Physical properties, H1‐NMR, F19‐NMR and IR spectra of these compounds are reported, along with their susceptibility to undergo rearrangements catalyzed by electrophiles.
Substituted 1,3‐dihydro‐4H‐furo[3,4‐d]‐1,3‐benzodiazepin‐3‐ones: Synthesis and scope of the method
Authors: Venturella Vincent S. , Watson Edward J.
Published: March 2009

The preparation of a series of 1,3‐dihydro‐4H‐furo[3,4‐d]‐1,3‐benzodiazepiri‐3‐ones has been studied. This study and the compounds prepared tend to illustrate that the limiting factor in the scope of the synthetic method is similar to that noted generally in the Fisher indole synthesis. The lactone ring is relatively stable under a variety of conditions, and is believed to lend ease of formation to the ring system studied.
Cyclic acylimines and cyclic carbinolamides 1. 2‐azaphenaiones.
Authors: Warshawsky A. , Ben‐Ishai D.
Published: March 2009

2‐Azaphenalone hydrochloride (VI), 2‐methyl‐1‐azaphenalonium chloride (XIV), 3‐phenyl‐2‐azaphenalone (XVIII) and 3‐phenyl‐2‐methyl‐2‐azaphenalonium chloride (XXI) were synthesized and their chemical and physical properties were studied. At room temperature they add weak nucleophiles (e.g., alcohols, amides) as well as compounds possessing active methylene groups. The methanol addition products (e.g., V) reacted thermally or in the presence of an acid catalyst with nucleophiles to give products identical with those obtained from the azaphenalone hydrochlorides.
A new linear notation system based on combinations of carbon and hydrogen
Authors: Skolnik Herman
Published: March 2009

A new linear notation system is described which was designed to have a one‐to‐one correspondence with the chemical structures represented by the notations. Each notation is unique and unambiguous, yet simple and compatible with computer input and output characters. The symbols used in the notation system denote carbon in terms of bonds and attached hydrogen(s). The notation system is illustrated with acyclic, carbocyclic, and heterocyclic examples.
Pyranylidene iminium salts II. Iminium salts derived from pyrones, dialkylamides and phosphorus oxychloride
Authors: Vanallan J. A. , Petropoulos C. C. , Reynolds G. A.
Published: March 2009

N,N‐Dialkylamides, pyrones, and phosphorus oxychloride react to give pyranylidene chloroiminium salts. The chlorine atom of these salts is readily displaced by nucleophiles to yield a variety of pyranylidene derivatives.
Chemistry of thienopyridines. VII. Mechanistic studies on the synthesis of thieno[2,3‐c] pyridine by thermolytic cyclization
Authors: Klemm L. H. , Mccoy D. R. , Shabtai J. , Kiang W. K. T.
Published: March 2009

A study was made of the formation of thieno[2,3‐c]pyridine (1) from hydrogen sulfide and 4‐vinylpyridine in a flow system at 630°. 2‐(4‐Pyridyl)ethanethiol and bis‐2‐(4‐pyridyl)ethyl sulfide were found to be likely intermediates. Based on these studies, there was devised a two‐step practical preparative method for I (optimum overall yield 58%) which consists of preliminary conversion of 4‐vinylpyridine to benzyl 2‐(4‐pyridyl)ethyl sulfide and subsequent thermolysis (at 605°) of this substance.
Aromatic substitution of 4‐phenylisothiazole
Authors: Finley Joseph H. , Volpp Gert P.
Published: March 2009

Aromatic substitutions on 4‐phenylisothiazole by nitric acid, halogens, chlorosulfonic acid and acetic anhydride take place under relatively mild conditions to give predominantly para and ortho substitution on the benzene ring. By contrast, the 3‐isothiazolyl group has been shown to be meta directing. Several derivatives of 4‐phenylisothiazole are described.
Electron‐impact induced fragmentation of alkylthiopyridines. The extent of ring nitrogen involvement
Authors: King Kenneth F. , Hershenson Fred M. , Bauer Ludwig , Bell Charles L.
Published: March 2009

The fragmentation patterns obtained upon electron impact of 2‐, 3‐, and 4‐alkylthio‐pyridines were examined to determine the extent that the ring nitrogen is involved. The effect of the size of the alkyl group, as well as the ring position of the sulfide on the fragmentation of the methyl‐, ethyl‐, n‐propyl‐, n‐butyl‐ and t‐butylthiopyridines, is discussed. The mass spectrum of 2‐n‐octylthiopyridine is also recorded.

The molecular ions decomposed with rupture of the bonds α, β, γ, and δ from the hetero‐aromatic ring. The molecular ions also exhibited the loss of alkenes via a number of mechanisms, notably the loss of Cn‐1 H2n from the alkyl group of 2‐alkylthiopyridines by a transition involving the rupture of a C‐C bond γ to the ring and the transfer of a proton on a carbon ϵ to the ring. The role of the pyridine sp2 nitrogen in this and other fragmentations is discussed. An elimination of HS radical is also observed in a number of these alkylthiopyridines.
Mannich and eschweiler‐clarke reaction of 1‐benzyl‐1,2,3,4‐tetrahydroisoquinolines. Studies on the syntheses of heterocyclic compounds. Part CCCXVIII
Authors: Kametani T. , Noguchi I. , Saito K.
Published: March 2009

Modified Mannich reactions of a number of 1‐benzyl‐1,2,3,4‐tetrahydroisoquinolines (Ia‐Ie) were attempted to afford the corresponding protoberberine derivatives (IIa‐IIe) in good yield. Treatment of both If and Ig with formalin under a variety of Mannich or Eschweiler‐Clarke conditions did not give the expected protoberberine derivatives IIf and IIg, but afforded the N‐methyl derivatives (VIIa) and (VIIb), respectively.
The synthesis of thiaolivacine and related compounds
Authors: Campaigne E. , Ashby John
Published: March 2009

1,5‐Dimethylbenzothieno[2,3‐g]isoquinoline (thiaolivacine) has been prepared from the nitro‐vinyl derivative of 4‐methyl‐3‐dibenzothiophenecarboxaldehyde. Using the same aldehyde, 4‐des‐methylisothiaolivacine was prepared by formation of the Schiff's base with aminoacetaldehyde diethyl acetal followed by cyclization. Similar methods yielded the pyrido‐N‐isomer, 1‐des‐methylthiaolivacine, from 4‐methyl‐2‐dibenzothiophenecarboxaldehyde. The thiaolivacine parent unsubstituted ring system, benzothieno[2,3‐g]isoquinoline, was prepared from 2‐dibenzothio‐pheneearboxaldehyde by the aminoacetaldehyde approach, as was the corresponding oxygen analog, benzofuro[2,3‐g]isoquinoline, from 2‐dibenzofurancarboxaldehyde. The 100 MHz spectra of these fused isoquinolines are recorded and correlated.
The deactivating effect of a meta‐methoxy group in the methoxydechlorination of pyridine and pyrimidine derivatives
Authors: Forchiassin M. , Illuminati G. , Sleiter G.
Published: March 2009

Reactivity data and the activation parameters for the methoxydechlorination of some 2‐chloro‐4‐R‐pyridines and 4‐chloro‐6‐R‐pyrimidines have been determined. A methoxy group meta with respect to the reaction site is found to be deactivating as already observed in the quinoline series. This gives further support to the hypothesis that in N‐heteroaromatic systems a conjugative interaction of an electron‐releasing substituent with the aza group (s) is a factor in modifying the nucleophilic reactivity as predicted by Hammett's σm values.
Reaction of α,β‐unsaturated acid chlorides with β‐diketones. Synthesis of 4,6,7,8‐tetrahydro‐2H‐1‐benzopyran‐2,5(3H)‐diones
Authors: Monroe Bruce M.
Published: March 2009

Reaction of an α,β‐unsaturated acid chloride with the anion of 5,5‐dimethyl‐1,3‐cyclohexane‐dione (2) gives either the enol ester (4) or a cyclized product (5), depending upon the reaction conditions. When the acid chloride is in excess, the ester is obtained. When the anion is in excess and the acid chloride is acryloyl or crotonyl, the cyclized product is obtained. A similar cyclized product (9) was formed from acryloyl chloride and an excess of the anion of 4‐hydroxy‐6‐methyl‐2‐pyrone (8).
The addition reaction of α‐azido ethers and α‐azido thioethers to phenylacetylene
Authors: Garcia‐Muñoz G. , Madroñero R. , Rico M. , Saldaña M. C.
Published: March 2009

Several v‐triazoles were synthesized by 1,3‐dipolar cycloaddition of certain α‐azido ethers and α‐azidothioethers to phenylacetylene. In most of the cases the reaction led to the formation of the two isomeric v‐triazoles. Structural assignments for the products obtained were made on the basis of NMR data and chemical reactions. Characteristic differences between the NMR spectra of the isomers have been noted.
Benzimidazolinetriones. Reactions of 2,5,6‐ and 2,4,7‐benzimidazolinetriones
Authors: March Louis C. , Joullié Madeleine M.
Published: March 2009

The condensation of 2,5,6‐benzimidazolinetrione with ethylenediamine resulted in the formation of the 1,3‐dihydro‐2H‐imidazo[4,5‐g]quinoxalin‐2‐one ring system. The reaction of this trione with excess ethanethiol resulted in the isolation of three hydroquinones which were oxidized to the respective quinones. 2,4,7‐Benzimidazolinetrione was shown to undergo a Diels‐Alder reaction with isoprene and a mono‐addition reaction with benzenethiol.
Novel animation reactions of dihydrofurano[2,3‐d] pyrimidines
Authors: Campaigne E. , Ellis R. L.
Published: March 2009

Although alkoxypyrimidines can be aminated to yield aminopyrimidines, monoamination of 2,4‐ or 4,6‐chloroalkoxypyrimidines results in chlorine displacement. Preferential alkoxy displacement in such systems is unusual. We now have evidence of such a displacement in the dihydrofurano[2,3‐d] pyrimidines (V). In some cases two types of products, formed by displacement of either the chlorine or alkoxy substituent, were obtained.
Reactions of 6‐hydrazino‐, 6‐hydroxylaminopurines and related derivatives
Authors: Giner‐Sorolla Alfredo
Published: March 2009

7H‐Tetrazolo[5,1‐i]purine was prepared by nitrosation of 6‐hydrazinopurine and by reaction of 6‐chloropurine with sodium azide; it was converted to adenine upon catalytic hydrogenation. 6‐Hydroxylaminopurine was oxidized to 6‐nitrosopurine with manganese dioxide, while alkaline treatment of the former gave 6,6′‐azoxypurine. Nitrosation of 6‐hydroxylaminopurine afforded 6‐(N‐nitroso)hydroxylaminopurine. Reaction of 6‐chloropurine with 6‐hydrazinopurine led to 6,6′‐bisadenine; the corresponding ribosyl derivatives gave 6,6′‐bisadenosine. Upon air oxidation, 6,6′‐bisadenine was converted into 6,6′‐azopurine. The related 6‐thiosemicarbazino‐ and 6‐(N‐methyl)ureidopurine derivatives are also described. 6‐N‐(Nitroso)hydroxylaminopurine showed an inhibitory activity against several mouse tumors and leukemias.
The synthesis of certain ribofuranosylindazoles
Authors: Revankar Ganapathi R. , Townsend Leroy B.
Published: March 2009

The synthesis of 1‐(β‐D‐ribofuranosyl)indazole (4), 2‐(β‐D‐ribofuranosyl)indazole (5) and 6‐, 5‐, and 4‐nitro‐2‐(β‐D‐ribofuranosyl)indazole (8a, 8b, and 8c, respectively), has been accomplished in good yield by the condensation of the appropriate N‐trimethylsilylindazole (1, 6a, 6b, and 6c) with 2,3,5‐tri‐O‐acetyl‐D ‐ribofuranosyl bromide (2) followed by subsequent deacetylation of the reaction products. The site of ribosylation and the assignment of anomeric configuration for all nucleosides reported is discussed. This has furnished the first indazole nucleosides with assigned anomeric configurations and the site of ribosylation has been established on the basis of uv comparisons with model methyl compounds.
Synthesis of 3‐aminosydnone imines
Authors: Götz M. , Grozinger K.
Published: March 2009

The synthesis and spectroscopic properties of 3‐aminosydnone imines are described.
Studies in the chemistry of 1,2,5‐oxadiazole (II). Synthesis and properties of furazanodiazepines
Authors: Gasco A. , Ruá G. , Menziani E. , Nano G. M. , Tappi G.
Published: March 2009

This paper describes the synthesis and the properties of some furazanodiazepine derivatives obtained by condensing the appropriate β‐diketones with 3,4‐diaminofurazan. On the basis of U.V., I.R. and N.M.R. evidence a mono‐imino structure is suggested for the compounds obtained.

Low temperature N.M.R. spectra suggest a rapid tautomensm for the dimethyl derivative.
Cleavage of NO bonds in 1,2,4‐oxadiazolines
Authors: Srimannarayana G. , Srivastava R. M. , Clapp Leallyn B.
Published: March 2009

The photochemical cleavage of the N‐O bond in 1,2,4‐oxadiazolines I to form acetamidines II was found to occur under mild conditions (ordinary light, 3560Å, or 2537Å). The weak N‐O bond in 3‐mcthyl‐4,5‐diphenyl‐1,2,4‐oxadiazoline (If) was also cleaved by catalytic reduction to give a molecular compound composed of benzyl alcohol and N‐phenylacetamidine, V.
The orientation in the ullmann‐fetvadjian acridine cyclizations with 2‐aminofluorene
Authors: Buu‐Hoï N. P. , Mangane M. , Jacquignon P.
Published: March 2009

2‐Aminofluorene is shown to undergo the Ullmann‐Fetvadjian acridine cyclization with α‐naphthol and paraformaldehyde at position 3, to give the linear indenoacridine; a similar reaction performed with β‐naphthol afforded a mixture of the corresponding linear and angular indenoacridines.
A new tetrahydroisoquinoline synthesis
Authors: Freter K. , Dubois E. , Thomas A.
Published: March 2009

Cyclization of 2‐vinylbenzylamines affords 1,2,3,4‐tetrahydroisoquinolines. The synthesis of the vinylbenzylamines from benzhydrols or isoindolones is described.
Synthesis of some amino‐substituted furanopyrimidines and styrylpyrimidines
Authors: Campaigne E. , Ho J. , Bradford Mary
Published: March 2009

5‐p‐Chlorophenyl‐6,6‐dimethyl‐5,6‐dihydro‐3H‐furano[2,3‐d]pyrimidine‐4‐one is readily converted to 4,6‐dichloro‐5‐β‐β‐dimethyl‐α‐ (p‐chlorostyryl)pyrimidine by warming in phosphorus oxychloride and acetic acid, behavior which is in strong contrast to that of the analogous 5‐phenyl derivative. The reaction provides a convenient source of 4‐amino‐6‐chloro‐5β,β‐dimethyl‐α‐ (p‐chlorostyryl)pyrimidines and 4,6‐diamino‐5‐β,β‐dimethyl‐α‐ (p‐chlorostyryl)pyrimidines, compounds of potential biological interest.
Trifluoromethylfurans II
Authors: Bambury R. E. , Miller L. F.
Published: March 2009

Ethyl acetoacetate reacted with 3‐bromo‐1,1,1‐trifluoro‐2‐propanone in the presence of base to give 3‐carbethoxy‐4,5‐dihydro‐4‐hydroxy‐2‐methyl‐4‐trifluoromethylfuran (I). Acid catalyzed dehydration of I gave the corresponding furan (III). Saponification of III gave 2‐methyl‐4‐trifluoromethyl‐3‐furoic acid which was decarboxylated to yield 2‐methyl‐4‐trifluoromethylfuran (V) for which a structure proof is presented. Conversion of the methyl groups of III and V to formyl groups is described.
A novel synthesis of 2,4‐thiophenediamines and their behavior as stable reactive enamines
Authors: Chupp John P.
Published: March 2009

Reaction of α‐chlorothioacetanilides (1) in refluxing methanol provides a new route to stable, reactive 2,4‐thiophenediamines (2). These materials display interesting chemical and physical properties, based in large part on the interaction of the anilino groups with nuclear substituents alpha to the thiophene sulfur. Thus 2 is easily protonated, with rapid exchange of the 5‐proton, while α‐carbon‐nitrogen cleavage has been observed for the first time during Raney nickel degradation. The susceptibility of the thiophenediamines to electrophilic attack is further demonstrated by facile formation of 3,5‐diamino‐2‐thiophene carboxanilides (3) and 3,5‐diamino‐2‐thienylphenyl ketones (4) from respective reaction of isocyanates, isothiocyanates, and acid chlorides with 2. Certain interesting and unusual spectral characteristics of these compounds, resembling enamines and enaminoketones, are presented and discussed.
Naphthyridine chemistry. XII. Syntheses of N‐oxides
Authors: Paudler William W. , Pokorny David J. , Cornrich Sandra J.
Published: March 2009

The syntheses of the various 1,X‐naphthyridine mono‐ and di‐N‐oxides as well as the 2‐mono‐and 2,7‐di‐N‐oxides of 2,7‐naphthyridine are reported. The PMR spectra of these compounds have been analyzed in detail.
Synthesis of 1,2‐disubstituted naphth [1,2‐d]imidazole‐4,5‐diones
Authors: Carroll F. I. , Blackwell J. T.
Published: March 2009

A convenient synthesis of 3‐acylamino‐1,2‐naphthoquinones (I) is presented. The addition of aromatic and aliphatic amines to I followed by exposure to oxygen gives the corresponding 4‐arylamino‐ or 4‐alkylamino‐3‐acylamino‐1,2‐naphthoquinones (II). The addition of 4‐cyclo‐hexylbutylamine to 3‐trichloroacetamino‐1,2‐naphthoquinone took an anomalous course and 1‐(4′‐cyclohexylbutyl)‐3(H)‐naphth[1,2‐d]imidazoline‐2,4,5‐trione (VII) was obtained.

Treatment of II with refluxing acetic acid gave 1,2‐disubstituted naphth[1,2‐d]imidazole‐4,5‐diones (III). The reaction was successful with a variety of 4‐substituted amino‐3‐acylamino‐1,2‐naphthoquinones (II) and usually occurred in excellent yield. However, the cyclization of II to III is subject to steric limitation and attempts to cyclize 4‐tert‐butylamino‐3‐acetamino‐1,2‐naphthoquinone to the corresponding imidazole derivative was unsuccessful. The infrared, ultraviolet and nuclear magnetic resonance spectra of I, II, and III are discussed in relation to their structures.
6(5H)‐phenanthridinones. II. Preparation of substituted 6(5h)‐phenanthridinones from 9‐oxofluorenes
Authors: Pan Hsi‐Lung , Fletcher T. Lloyd
Published: March 2009

A number of 6(5H)‐phenanthridinones have been conveniently prepared from 9‐oxofluorenes through the Schmidt reaction. It has been found that all amino and nitro 9‐oxofluorenes thus far tried gave substituted 6(5H)‐phenanthridinones with the amino or nitro group situated in the benzene ring attached to the nitrogen of the lactam group. UV and IR spectral data are presented for these compounds.
The synthesis of 3‐deazapyrimidine nucleosides related to uridine and cytidine and their derivatives
Authors: Currie Bruce L. , Robins Roland K. , Robins Morris J.
Published: March 2009

Condensation of 2,4‐bis(trimethylsilyloxy)pyridine (1) with 2,3,5‐tri‐O‐benzoyl‐D‐ribofuranosyl bromide (2) gave 4‐hydroxy‐1‐(2,3,5‐tri‐O‐benzoyl‐β‐D‐ribofuranosyl)‐2‐pyridone (3). Deblocking of 3 gave 4‐hydroxy‐1‐β‐D‐ribofuranosyl‐2‐pyridone (3′‐deazauridine) (4). Treatment of 4 with acetone and acid gave 2′,3′‐O‐isopropylidene‐3‐deazauridine (6). Reaction of 4 with diphenylcarbonate gave 2‐hydroxy‐1‐β‐D‐arabinofuranosyl‐4‐pyridone‐O2←2′‐cyclonucleoside (7) which established the point of gylcosidation and configuration of 4. Base‐catalyzed hydrolysis of 7 gave 4‐hydroxy‐1‐β‐D‐arabinofuranosyl‐2‐pyridone (3‐deazauracil arabinoside) (12). Fusion of 1 with 3,5‐di‐O‐p‐toluyl‐2‐deoxy‐D‐erythro‐pentofuranosyl chloride (5) gave the blocked anomeric deoxynucleosides 8 and 10 which were saponified to give 4‐hydroxy‐1‐(2‐deoxy‐β‐D‐erythro‐pentofuranosyl)‐2‐pyridone (2′‐deoxy‐3‐deazauridine) (11) and its α anomer (9). Condensation of 4‐acetamido‐2‐methoxypridine (13) with 2 gave 4‐acetamido‐1‐(2,3,5‐tri‐O‐benzoyl‐β‐D‐ribofuranosyl)‐2‐pyridone (14) which was treated with alcoholic ammonia to yield 4‐acetamido‐1‐β‐D‐ribofuranosyl‐2‐pyridone (15) or with methanolic sodium methoxide to yield 4‐amino‐1‐β‐D‐ribofuranosyl‐2‐pyridone (3‐deazacytidine) (16). Condensation of 13 and 2,3,5‐tri‐O‐benzyl‐D‐arabinofuranosyl chloride (17) gave the blocked nucleoside 22 which was treated with base and then hydrogenolyzed to give 4‐amino‐1‐β‐D‐arabinofuranosyl‐2‐pyridone (3‐deazacytosine arabinoside) (23). Fusion of 13 with 5 gave the blocked anomeric deoxynucleosides 18 and 20 which were deblocked with methanolic sodium methoxide to yield 4‐amino‐1‐(2‐deoxy‐β‐D‐erythro‐pentofuranosyl)‐2‐pyridone (2′‐deoxy‐3‐deazacytidine) (21) and its a anomer 19. The 2′‐deoxy‐erythro‐pentofuranosides of both 3‐deazauracil and 3‐deazacytosine failed to obey Hudson's isorotation rule but did follow the “quartet”‐“triplet” anomeric proton splitting pattern in the 1H nmr spectra.
A synthesis of O‐ethylcularidine (studies on the syntheses of heterocyclic compounds. Part cccxxxiii
Authors: Kametani Tetsuji , Iida Hideo , Kibayashi Chihiro
Published: March 2009

In order to confirm the structure of cularidine (I), O‐ethylcularidine (II) was synthesized and shown to be identical with the naturally occurring O‐ethyleularidine on the basis of NMR spectroscopy and the Rf values.
Chemistry of thienopyridines. IX. Direct nitration of thieno[2,3‐b]pyridine and thieno[3,2‐b] pyridine
Authors: Klemm L. H. , Zell Reinhard , Barnish I. T. , Klemm R. A. , Klopfenstein C. E. , Mccoy D. R.
Published: March 2009

Thieno[ 2,3‐b]pyridine (I) and thieno[3,2‐b]pyridine (II) were nitrated at C‐3 in ca. 50% yield by means of nitric‐sulfuric acids. Reduction of 3‐nitro‐I (Ia) with tin and hydrochloric acid gave 3‐amino‐I (Ib) (39%), which was converted to 3‐acetylamino‐I (Ic) and to dipyrido[2,3‐b:2′,3′‐d]thiophene (V). Reduction of 3‐nitro‐II (IIa) with iron and acetic acid at 100° gave 3‐acetyl‐amino‐II (IIb) (25%), while use of tin and hydrochloric acid at room temperature gave 2‐chloro‐3‐amino‐II (IIc). Assignments of position of nitration are based on nmr spectral data (which indicate. that substitution occurs in the thiophene ring) and on non‐identities of Ic, IIb, and V with authentic samples of 2‐acetylamino‐I, 2‐acetylamino‐II, and dipyrido[2,3‐b:3′,2′‐d]thiophene (VI), respectively. Results are consistent with reactivity indices for I and II as calculated from simple Hückel Molecular Orbital theory and with observations on nitration and reduction in the isoteric quinoline system.
Dithietanes. Synthesis of N‐substituted 2‐imino‐1,3‐dithietanes and 2‐imino‐1,3‐dithietane hydrochloride
Authors: Addor Roger W.
Published: March 2009

The reaction of diethylphosphoryl isothiocyanate with potassium hydrosulfide gave potassium diethoxyphosphinyldithiocarbamate (3a). This salt, with methylene bromide, afforded 2‐diethoxyphosphinylimino‐1,3‐dithietane (5a) in high yield. In concentrated hydrochloric acid, 5a was hydrolyzed to 2‐imino‐1,3‐dithietane which was isolated as a stable hydrochloride (7). The synthesis of some other N‐Substituted 2‐imino‐1,3‐dithietanes is also described.
The structure of the cations from 2– and 4‐pyrimidones
Authors: Shoffner James P. , Bauer Ludwig , Bell Charles L.
Published: March 2009

An infrared spectral investigation of a number of pyrimidine and pyrimidone hexachloroantimonates is reported. Typical aromatic absorption bands found in pyrimidinium salts were absent in the pyrimidone cations. 2‐And 4‐Pyrimidone hexachloroantimonates, as well as their N‐methyl‐ and N,N'‐dimethyl derivatives, exhibit intense carbonyl absorption bands between 1720–1729 cm−1 (solid state) which corroborates N‐protonation of pyrimidones.
Total synthesis of (±)‐obaberine [studies on the syntheses of heterocyclic compounds. Part CCCXLIX ]
Authors: Kametani Tetsuji , Wakisaka Kikuo , Kigasawa Kazuo
Published: March 2009

Cyclization of one of two cyclic bisamides (III and IX), followed by reduction and successive methylation, gave our expected bis‐coclaurine derivatives, one of which was identical with O‐methyloxyacanthine, namely natural obaberine (I).
Dihydrocytosines and cytokines from 3‐aminopropionitriles
Authors: Doub Leonard , Krolls Uldis
Published: March 2009

The synthesis of dihydrocytosines 4 from 3‐aminopropionitriles 1 has been broadened and the dihydrocytosines themselves have now been successfully converted to cytosines 9. Unsubstituted 3‐(H, alkyl or aryl) aminopropionitriles (1, X = H) convert with cyanate to 1‐(H, alkyl or aryl)‐1‐(2‐cyanoethyl)ureas (2, X = H), which in turn easily cyclize with anhydrous strong acid or base to 1‐(H, alkyl or aryl)‐5,6‐dihydrocytosines (4, X = H). The 1‐arylaminopropionitriles (1, X = H) which are poorly reactive with cyanic acid combine readily with benzoylureas to form 3‐benzoyl‐1‐(2‐cyanoethyl)‐1‐arylureas (3, X = H). These benzoylureas likewise cyclize with strong acid or base but with simultaneous elimination of the benzoyl moiety to yield the 1‐aryldihydrocytosines 4 (X = H). Amines have successfully been added to 2‐chloroacrylonitrile to yield 2‐chloro‐3‐(amino and substituted amino)propionitriles (1, X = Cl). These 2‐chloropropionitriles also could be converted with cyanate or benzoylisocyanate to ureas and benzoylureas, respectively (1‐(H or alkyl)‐1‐(2‐chloro‐2‐cyanoethyl)ureas (2, X = Cl) or 1‐(H or alkyl)‐1‐(2‐chloro‐2‐cyanoethyl)‐3‐benzoylureas (3, X = Cl). The chlorine substituted ureas were unstable especially to base and to heat but with anhydrous acid were cyclized in high yield to 1‐(H or alkyl)‐5‐chloro‐5,6‐dihydro‐cytosines (4, X = Cl). Direct chlorination of unsubstituted dihydrocytosines 4 (X = H) did not afford these same 5‐chlorodihydrocytosines 4 (X = Cl) under any conditions investigated. 1‐Ethyl‐5,6‐dihydrocytosine (4b) as the cation (hydrobromide) is converted directly in good yield to 1‐ethylcytosine hydrobromide (7) by bromine in nitrobenzene at 140‐160° in a concomitant bromination dehydrobromination reaction. 1‐(Alkyl or aryl)‐5,6‐dihydrocytosines (4, X = H) are halogenated at low temperature in the presence of base to form (N3 or N4)halogenodihydrocytosines (8, R = H). The N‐chlorodihydrocytosines 8 are stable. The N‐bromo and N‐iodo compounds isomerize spontaneously to 5‐halogeno‐5,6‐dihydrocytosines (4, X = Br, I; R = H). The 5‐halogeno‐5,6‐dihydrocytosines 4 (X = Cl, Br, I) whether from cyclization or direct halogenation are readily dehydrohalogenated to the corresponding cytosines 9.
1,4‐Cycloaddition reactions. III. Synthesis of furo[3,2‐c]pyrido[2,3‐g]quinolines, Furo[2,3‐a] [4,7]phenanthrolines, Furo[3,2‐c]pyrrolo[2,3‐g]quinolines, Furo[3,2‐c]pyrrolo[3,2‐g]quinolines, and Furo[3,2‐c]furo[2′,3′:4,5]pyrido[2,3‐g]quinolines from 2,3‐dihydro‐5‐methylfuran and schiff bases
Authors: Perricone S. C. , Worth Donald F. , Elslager Edward F.
Published: March 2009

The 1,4‐cycloaddition of 2,3‐dihydro‐5‐methylfuran (II) to 1‐acetyl‐1,2,3,4‐te trahydro‐6‐[(p‐hydroxybenzylidene)amino]quinoline (VIII) in the presence of boron trifluoride gave two pairs of epimers, namely dl‐10‐acetyl‐2,3,3a,4,5,7,8,9,10,11b‐decahydro‐4‐(p‐hydroxyphenyl)‐11b‐methylfuro[3,2‐c]pyrido[2,3‐g]quinoline (IXa and b) and dl‐8‐acetyl‐2,3,3a,4,5,8,9,10,11,‐11c‐decahydro‐4‐(p‐hydroxyphenyl)‐11c‐methylfuro[2,3‐a][4,7]phenanthroline (Xa and b). dl‐9‐Acetyl‐3,3a,4,5,7,8,9,10b‐octahydro‐4‐(p‐hydroxyphenyl)‐10b‐methyl‐2H‐furo[3,2‐c] pyrrolo‐[2,3‐g]quinoline (XIIIa) was the predominant product isolated from the reaction of II with 1‐acetyl‐5‐[p‐(hydroxybenzylidene)amino]indoline (XII). When 1‐acetyl‐6‐[(p‐hydroxybenzylidene)amino]indoline (XVI) was treated with 2,3‐dihydro‐5‐methylfuran (II), two epimers of dl‐7‐acetyl‐3,3a,4,5,7,8,9,10b‐octahydro‐4‐(p‐hydroxyphenyl)‐10b‐methyl‐2H‐furo[3,2‐c]pyrrolo[3,2‐g]quinoline (XVIIa and b) were obtained. dl‐2,3,3a,4,5,6b,8,9,9a,10,11,12b‐Dodecahydro‐4,10‐bis(p‐methoxyphenyl)‐6b,12b‐dimethylfuro[3,2‐c]furo[2′,3′:4,5]pyrido[2,3‐g]quinoline (XX) was formed when 2,3‐dihydro‐5‐methylfuran was allowed to react with N,N'‐bis(p‐methoxybenzylidene)‐p‐phenylcnediamine (XIX). Structure assignments were made from NMR spectra. None of the compounds exhibited appreciable biological activity.
2H‐1,4‐benzothiazines from the reaction of 2‐aminoethanethiol with nascent 4‐methyl‐o‐benzoquinone
Authors: Prota G. , Petrillo O. , Santacroce C. , Sica D.
Published: March 2009

4‐Methyl‐o‐benzoquinone, generated oxidatively, reacts readily with 2‐aminoethanethiol giving 5‐hydroxy‐7‐methyl‐1,3,4‐dihydro‐2H‐1,4‐benzothiazine (I) or 5‐oxo‐7‐methyl‐8‐(2‐hydroxy‐4‐methylphenoxy)‐3,5‐dihydro‐2H‐1,4‐benzothiazine (VIII), depending on the conditions under which the reaction is performed. Chemical and spectral (uv, ir, nmr and ms) evidence for the assigned structures, as well as the course of the above mentioned reaction is described.

A study of the behaviour of compound VIII in the presence of acids and alkalies is also reported.
Reaction of cis‐2,3‐dioctylaziridine with carboxylic acids
Authors: Maerker G. , Haeberer E. T. , Donahue E. T. , Foglia T. A.
Published: March 2009

A series of aliphatic and aromatic carboxylic acids reacted with 2,3‐dioctylaziridine to yield β‐hydroxyalkyl amides in 69–89% yields and 2‐substituted 4,5‐di‐n‐octyl‐δ2‐oxazolines in amounts ranging from traces to 12% of the theoretical. No correlation could be found between carboxylic acid strength and either hydroxyamide or δ2‐oxazoline yields. Solvents affected the product distribution.
2,5‐diphenyl‐3‐morpholinofuran and its 2‐hydro, 2‐bromo and 2‐hydroxymorpholinofurylium salts
Authors: Lutz R. E. , Hankins W. M. , Hankins M. G. , Welstead W. J. , Dickerson C. L.
Published: March 2009

2,5‐Diphenyl‐3‐morpholinofuran (1) reacts with bromine and trifluoroacetic acid, giving respectively 2‐bromo and 2‐hydro furylium salts (2,3). The 2‐hydroxy furylium bromide (4) was obtained by reaction of cis‐morpholino‐1,2‐dibenzoylethylene (5) with hydrogen bromide. The nmr spectra of these salts show differences between the two morpholino dimethylene moieties of each caused by restricted rotation at the 3‐immonium group. Chemical relationships studied include reductions to the morpholinofuran, conversions to 3‐furanones, and the slow reaction of morpholinodibenzoylethylene with phenylmagnesium bromide to give cis‐dibenzoylstyrene (13).
Proton magnetic resonance studies of compounds with bridgehead nitrogen atoms. XIV .: The influence of an axial 5‐methyl group on the chemical shifts of C2 methylene protons in 1,3‐heterosystems
Authors: Crabb T. A. , Chivers P. J. , Jones E. R. , Newton R. F.
Published: March 2009

The shielding of a C‐2 axial proton by an axial C‐5 methyl group in 1,3‐heterocyclic systems is described and explained in terms of conformational distortion.
Pyridazines. XXXIV. Electron‐impact induced fragmentation of some s‐triazolo[4,3‐b] pyridazines, tetrazolo[1,5‐b] pyridazines and related compounds
Authors: Pirc V. , Stanovnik B. , Tišler M. , Marsel J. , Paudler W. W.
Published: March 2009

Mass spectra of several 4‐triazolo[4,3‐b]pyridazines and tetrazolo[1,5‐b]pyridazines were examined in order to establish their fragmentation patterns. Two distinct patterns could be observed upon electron impact of s‐triazolo[4,3‐b]pyridazines and tetrazolo[1,5‐b]pyridazines. Azidotetrazolopyridazines show a loss of six nitrogens. This can be accounted for by a path proceeding via a molecular ion with a bis‐tetrazolo structure.
The synthesis of certain 4‐mono‐ and 4,7 dihydroxy‐1,10‐phenanthrolines
Authors: Case Francis H.
Published: March 2009

Aminocrotonates and cinnamates formed by the action of ethyl acetoacetate and ethyl benzoylacetate on substituted 8‐aminoquinolines have been cyclized to 4‐hydroxy and 4,7‐dihydroxy‐1,10‐phenanthrolines.
Mass spectra of some aminonaphthyridines and aminoquinolines
Authors: Brown Ellis V. , Plasz Andrew C. , Mitchell Stanley R.
Published: March 2009

The mass spectra of all the aminoquinolines, the 2–, 3– and 4‐amino‐1,5‐naphthyridines, some amino‐1,6‐naphthyridines, and two amino‐1,8‐naphthyridines with methyl substituents are reported. The major fragment in the aminoquinolines is formed by the loss of HCN from the molecular ion. The most abundant fragment in the aminonaphthyridines is formed by the loss of HCN from the molecular ion except in the 2‐amino‐1,5‐naphthyridine isomer. In both 1,8‐naphthyridine isomers investigated, the loss of C2H2 is an alternate fragmentation pathway of significance. In all of the compounds investigated, the loss of the primary amino group from the molecular ion was found to be an insignificant fragmentation.
Crystal and molecular structure of cis 11‐(p‐iodobenzenesulfonyl)‐11‐azabicyclo[8.1.0]undecane
Authors: Zacharis H. , Trefonas L. M.
Published: March 2009

The crystal and molecular structure of the title compound was determined by single‐crystal x‐ray diffraction techniques. The compound crystallizes in the orthorhombic space group Pca21, with four molecules in a unit cell of dimensions a = 17.552 ± .003, b = 8.235 ± .0008 and c = 11.914 ± .001 Å. The structure was solved by the heavy atom method and refined by full matrix least squares to a final value of R = 0.055 for the 740 independently measured, statistically significant reflections. The conformation of the cyclodecane ring in the bicyclic system differs from the idealized cyclodecane ring based on conformational studies and previous x‐ray determinations of simpler systems. The differences in conformation are discussed.
Azabicyclo chemistry II. Synthesis of 1,5‐methano‐2,3,4,5‐tetrahydro‐1H‐2‐benzazepines. B‐norbenzomorphans
Authors: Mokotoff Michael , Jacobson Arthur E.
Published: March 2009

The syntheses of the B‐norbenzomorphans, 1,5‐methano‐2,3,4,5‐tetrahydro‐1H‐2‐benzazepine (1a) and itsN‐methyl derivative (Ib) were accomplished. Phenylsuccinic anhydride (III) was cyclized to 3‐carboxy‐1‐indanone (IVa), which was converted by the Arndt‐Eistert method to the homologous methyl indanone‐3‐acetate (V). One experiment in the synthesis of V led to the by‐products 3‐carboxamido‐1‐indanone (IVd) and 3‐(N‐methylcarboxamido)‐1‐indanone (IVe), identified by physical and chemical means. Methyl 1‐aminoindan‐3‐acetate (VII) was prepared by catalytic reduction of methyl indanone‐3‐acetate oxime (VI). Hydrolysis of VII afforded 1‐aminoindan‐3‐acetic acid (VIII), which was cyclized with dicyclohexylcarbodiimide to 1,5‐methano‐2,3,4,5‐tetrahydro‐1H‐2‐benzazepin‐3‐one (IX). Reduction (lithium aluminum hydride) of IX gave amine Ia which was then methylated to Ib. The mass spectral fragmentation patterns of IX and Ia are discussed.
The formation of the indolizino[1,2‐c]quinolinium system by a novel nucleophilic reaction
Authors: Bradsher Charles K. , Burnham Weldon S. , Zinn Mary F.
Published: March 2009

2‐Methyl‐3‐(2‐pyridyl)quinoline (1) with a bromomethyl ketone or ethyl bromoacetate yields 6‐methyl‐12‐acylindolizino[1,2‐c]quinolinium bromides (5–9). The acyl derivatives can be deacylated in acid yielding 6‐methyl indolizino[1,2‐c]quinolinium salts (4). Benzoylation of 4 yields the 12‐benzoyl derivative (6).

The deacylation product (4) has been synthesized from 2‐acetamidophenacyl bromide (10) and 2‐pyridylacetone (12).
Pyrrolopyrimidine nucleosides. VI. Synthesis of 1,3 and 7‐β‐D‐ribofuranosylpyrrolo[2.3‐d] pyrimidines via silylated intermediates
Authors: Tolman Richard L. , Tolman Glen L. , Robins Roland K. , Townsend Leroy B.
Published: March 2009

The ribosylation of several silylated pyrrolo[2,3‐d]pyrimidines by the Wittenberg procedure has produced 1,3 and 7‐ribosylpyrrolo[2,3‐d]pyrimidine derivatives in high yield. Structure assignments have been made on the basis of the ultraviolet spectra of model compounds and further confirmed by chemical conversion to derivatives of established structure. A convenient ribosylation procedure utilizing silver oxide, a halosugar, and a silylated pyrrolo[2,3‐d]pyrimidine derivative in acetonitrile has been described.