bluuebunny/crossref_metadata_2025 huggingface dataset:
The use of NMR measurements in the orientation of pyrrolic substitution in 5,6‐dihydro‐7‐methyl‐6‐oxopyrrolo[1,2a]‐[3,1,6]benzothiadiazocine
Authors: Cobb J. , Cheeseman G. W. H. , Varvounis G.
Published: May 2009

The title compound 1, has been shown to give a 1‐bromo derivative 2 when subjected to free‐radical bromination and a 1‐dimethylaminomethyl derivative 3 by reaction under standard Mannich conditions. Vilsmeier formylation, however, furnishes the 3‐substituted derivative 4.
Anticancer anthrapyrazoles. Improved syntheses of clinical agents CI‐937, CI‐941, and piroxantrone hydrochloride
Authors: Beylin Vladimir G. , Colbry Norman L. , Goel Om P. , Haky Jerome E. , Johnson Donald R. , Johnson Judith L. , Kanter Gerald D. , Leeds Robert L. , Leja Boguslawa , Lewis Edward P. , Rithner Christopher D. , Showalter H. D. Hollis , Sercel Anthony D. , Turner William R. , Uhlendorf Susan E.
Published: May 2009

Improved processes for the synthesis of bulk quantities of the anthrapyrazole clinical agents CI‐937, CI‐941, and piroxantrone hydrochloride are reported. Reported also are detailed analytical and spectroscopic data for these agents and intermediates of the synthetic sequences.
Synthesis of ortho‐substituted aminopyridines. Metalation of pivaloylamino derivatives
Authors: Estel L. , Linard F. , Marsais F. , Godard A. , Quéguiner G.
Published: May 2009

The three isomeric pivaloylaminopyridines were lithiated in more than 80% yields. Aminopyridine derivatives were treated by 2.5‐3 equivalents of the complex BuLi‐TMEDA at −10° in diethyl ether. Reaction of the lithiated species with various electrophiles afforded a number of ortho‐substituted pivaloylaminopyridines in good yields. Secondary pyridine alcohols were oxidized to the corresponding aminopyridyl ketones. Pyridopyrimidines, benzonaphthyridines as well as an analogue of the natural antitumor alkaloid ellipticine has been synthesized showing the versatility of the method.
A simplified procedure for preparing 3,5‐disubstituted‐1,2,4‐oxadiazoles by reaction of amidoximes with Acyl chlorides in pyridine solution
Authors: Chiou Shishue , Shine Henry J.
Published: May 2009

3‐R‐5‐R′‐1,2,4‐Oxadiazoles are prepared in fair to good yield by short‐time, one‐pot reaction of an amidoxime, RC(NH2)NOH, with an acyl chloride, R'COCl, in pyridine solution. Precipitation of the oxadiazole occurs on diluting the pyridine reaction solution with water. Ordinary acyl chlorides can be used; they do not have to be unusually reactive to succeed in the one‐pot preparation. The procedure is simpler and more convenient than the conventional one, namely isolation and thermal rearrangement of an O‐acylamidoxime.
Amidrazones. 12. Formation of 3‐acylamino‐4,5‐dihydro‐1,1‐dimethyl‐1H‐pyrazolium salts by acid‐promoted cyclization of N3‐acylated derivatives of acrylamide dimethylhydrazone and (E)‐cinnamamide dimethylhydrazone
Authors: Smith Richard F. , Augustine Brian H. , Dennis Lisa A. , Ryan William J. , Liptak Stephen C. , Capparelli Brian R.
Published: May 2009

N3‐Acylated derivatives of acrylamide dimethylhydrazone 3a,b and (E)‐cinnamamide dimethylhydrazone 3c,d cyclized, on treatment with hydriodic acid or p‐toluenesulfonic acid, to give 3‐acylamino4,5‐dihydro‐1,1‐dimethyl‐1H‐pyrazolium salts 4a‐d.
Reactions of some quinazoline compounds with ethoxymethylenemalonic acid derivatives
Authors: Deady Leslie W. , Mackay Maureen F. , Werden Dianne M.
Published: May 2009

The reactions of ethyl (1,4‐dihydro‐4‐oxoquinazolin‐2‐yl)acetate 4 and 2‐aminoquinazolin‐4(1H)‐one 5 with diethyl ethoxymethylenemalonate (EMME), (ethoxymethylene)malononitrile (EMMN) and ethyl (ethoxymethylene)cyanoacetate (EMCA) are reported, and rather different results are obtained to those previously found with quinoline analogs. Reaction of 4 with EMME gives a pyrido[1,2‐a]quinazoline, while with EMMN and EMCA ethyl 2‐(pyridin‐2‐yl)aminobenzoates are formed, presumably by ring‐opening of intermediate pyrido[2,1‐b]quinazolines. Reaction of 5 with EMME likewise results in ultimate cyclization onto N‐1 of the quinazoline, while the EMMN and EMCA reactions give isolable pyrimido[2,1‐b]quinazolines. These are readily cleaved under mild conditions.
Pyridazines with heteroatom substituents in position 3 and 5. 3. 2‐aryl‐5‐hydroxypyridazin‐3(2H)‐ones as potential herbicides: Synthesis and some reactions
Authors: Schober Bernt D. , Megyeri Gabor , Kappe Thomas
Published: May 2009

The coupling of dimethyl acetonedicarboxylate 1 with a variety of aryldiazonium salts 2a‐i produces the hydrazones 3a‐i which can be cyclized in boiling dichlorobenzene to yield the pyridazone esters 4a‐i, or in sodium hydroxide solution to give the pyridazone acids 5a‐f,h,i, which can be decarboxylated at elevated temperatures. The hydroxy group in 4a,d can be acylated, sulfonated or alkylated yielding compounds 8a‐n. Condensation of 4a,d with magic malonates 9a‐d produces the pyronopyridazinones 10a‐f. The reaction of 4a with hydrazine yields the hydrazide 12 via the salt 11, and with ammonia the amide 14.
Synthesis of 1,2,4‐triazole, 1,2,4‐triazolo[3,4‐b][1,3,4]thiadiazole and 1,2,4‐triazolo[3,4‐b][1,3,4]thiadiazine derivatives of benzotriazole
Authors: El‐Khawass S. M. , Habib N. S.
Published: May 2009

A novel series of 1‐(1‐carbonylmethyl‐1H‐benzotriazole) thiosemicarbazides 3a‐e was synthesized and then cyclized with sodium hydroxide to afford 1‐(4‐substituted‐4H‐1,2,4‐triazole‐3‐thion‐5‐yl)methyl‐1H‐benzotriazoles 4a‐e, which were alkylated with ethyl iodide to l‐(3‐ethylthio‐4‐substituted‐4H‐1,2,4‐triazol‐5‐yl)‐methyl‐1H‐benzotriazoles 5b‐e. The reaction of 1H‐benzotriazol‐1‐acetic acid hydrazide (2) with carbon disulphide and potassium hydroxide followed by hydrazine hydrate gave 1‐(4‐amino‐4H‐1,2,4‐triazole‐3‐thion‐5‐yl)methyl‐1H‐benzotriazole (6). Its subsequent condensation with carboxylic acids in the presence of phosphorus oxychloride or with phenacyl bromides afforded two series of fused heterocycles namely; 6‐substituted‐3‐[1‐(1H‐benzotriazole)methyl]‐1,2,4‐triazolo[3,4‐b][1,3,4]thiadiazoles 7a‐e and 6‐substituted phenyl‐3‐[1‐(1H‐benzotriazole)methyl]‐7H‐1,2,4‐triazolo[3,4‐b][1,3,4]thiadiazines 8a‐e respectively. The structure of the newly synthesized compounds was elucidated by elemental analyses, ir and nmr spectra.
Color change (yellow \documentclass{article}\pagestyle{empty}\begin{document}$\rightleftharpoons$\end{document} orange) of 4,6,7‐tri(alkoxy‐substituted aryl)‐1,2,5‐thiadiazolo[3,4‐c]pyridines in the solid phase
Authors: Mataka Shuntaro , Takahashi Kazufumi , Tashiro Masashi , Lin Wei‐Hua , Iwasaki Shin‐Ichi , Tsutsui Tetsuo , Saito Shogo , Akiyama Shinji , Yonemitsu Tadashi
Published: May 2009

Reversible color change of 4,6,7‐tri(alkoxy‐substituted phenyl)‐1,2,5‐thiadiazolo[3,4‐c]pyridines 5 in the solid state was observed: on grinding, yellow crystals of 5 became an orange amorphous solid which, on heating or washing with an appropriate solvent, gave the original yellow crystals.
Synthesis of an acetyl‐α‐thio‐β‐carboline by thermolysis of dithio‐2,2′‐di(N′‐acetyltryptamine)
Authors: Barbier Michel , Devys Michel
Published: May 2009

The first synthesis of an acetyl‐α‐thio‐β‐carboline [2‐acetyl‐2,9‐dihydro‐1,2‐thiazino[6,5‐b]indole (4) 28%] by the thermolysis of dithio‐2,2′‐di(N′‐acetyltryptamine) 3 is reported. Deacetylation of 4 carried out in basic or acidic media does not lead to the free base but to a series of unidentified degradation products. This new substance 4 is therefore stabilized by the N‐acetyl group. The results so far obtained are discussed and a mechanism is proposed for the cyclisation produced by the thermolysis.
Synthesis and characterization of macrocyclic ligands containing benzene and/or pyridine rings and their nickel(II), copper(II) and zinc(II) complexes
Authors: Hashimoto Mamoru , Tagami Hidetoshi , Sakata Kazunori
Published: May 2009

Macrocycles, 7,16‐diethyl‐5,6,7,8,9,14,15,16,17,18‐decahydrodibenzo[b,i][1,4,8,11]tetraazacyclotetradecine (2B), 7,16‐diethyl‐5,6,7,8,9,14,15,16,17,18‐decahydro‐(E)dipyrido[b,i][1,4,8,11]tetraazacyclotetradecine (2E) and 7,16‐diethyl‐5,6,7,8,9,14,15,16,17,18‐decahydro‐(Z)‐dipyrido[b,i][1,4,8,11]tetraazacyclotetradecine (2Z), have been synthesized by hydrogenation of 7,16‐diethyl‐5,14‐dihydrodibenzo[b,i][1,4,8,11]tetraazacyclotetradecine and 7,16‐diethyl‐5,14‐dihydro‐(E)‐ or ‐(Z)‐dipyrido[b,i][1,4,8,11]tetraazacyclotetradecine. In each case, two isomers were produced with differing orientations of the ethyl groups relative to the macrocyclic plane. The isomers were separated by repeated recrystallization. Carbon‐13 nmr spectra for the metal‐free ligands were used to distinguish between the two isomers. The nickel(II), copper(II) and zinc(II) complexes of the two isomers of 2B were prepared and their spectroscopic data were determined. The ligand‐field bands in the 15000–30000 cm−1 region for the nickel(II) and copper(II) complexes are consistent with square‐planar configurations. A strong band appearing at ca. 3200 cm−1 in the infrared spectra was assigned to the N‐H stretching mode which shifted to lower frequency upon metal coordination.
Substituent effects on the photocycloaddition reactions of phenol to benzonitriles
Authors: Al‐Jalal N. A.
Published: May 2009

Methoxy‐, methyl‐, and chloro‐substituted benzonitriles undergo photocycloaddition to phenol to give substituted 1,2‐dihydroazocin‐2‐ones III, by initial attack of the cyano group on the aromatic ring of the phenol. The efficiency of the photocycloaddition reaction varied with the position of the substituents, with the para‐substituted ones giving the largest amount of photoproduct.
Diheterocyclic compounds from dithiocarbamates and derivatives thereof. V. 4,4′‐dioxo‐2,2′‐dithioxo(dioxo)‐6,6′‐biquinazolines
Authors: Garín Javier , Meléndez Enrique , Merchán Francisco L. , Merino Pedro , Orduna Jesús , Tejero Tomás , Viñegra Milagros
Published: May 2009

The title compounds 3, 5 and 9 were synthesized in a one step procedure from dithiocarbamates 2 or dithiocarbonimidates 7 in medium to high yields. The usefulness of 2 and 7 as synthetic equivalents of unstable or unavailable isocyanates and isothiocyanates is also discussed.
Synthesis of dl‐guinesines and related compounds
Authors: Mitsudera Hiroyuki , Uneme Hideki , Okada Yoshiyuki , Numata Mitsuo , Kato Atsushi
Published: May 2009

Guinesines A, B and C were synthesized starting from 1,3‐bis(benzylthio)‐2‐propanone and N‐methyl‐2,2‐diethoxypyrrolidine.
Synthesis of acyclic nucleoside analogs of 6‐substituted 2‐aminopurines and 2‐amino‐8‐azapurines
Authors: Párkányi Cyril , Yuan Hui Liang
Published: May 2009

Several new acyclonucleoside purine and 8‐azapurine analogs have been prepared from 2‐amino‐4,6‐dichloropyrimidine (1) and 3‐amino‐1,2‐propanediol (2a) and 4‐amino‐1‐butanol (2b), respectively, as the starting materials. The new target compounds are: 2‐amino‐6‐chloro‐9‐(2,3‐dihydroxypropyl)purine (6a), 2‐amino‐6‐chloro‐9‐(4‐hydroxybutyl)purine (6b), 2‐amino‐6‐chloro‐9‐(2,3‐dihydroxypropyl)‐8‐azapurine (7a), 2‐amino‐6‐chloro‐9‐(4‐hydroxybutyl)‐8‐azapurine (7b), 9‐(2,3‐dihydroxypropyl)‐8‐azaguanine (8a), 9‐(4‐hydroxybutyl)‐8‐azaguanine (8b), 9‐(2,3‐dihydroxypropyl)‐8‐azathioguanine (9a), and 9‐(4‐hydroxybutyl)‐8‐azathioguanine (9b). Also, the requisite intermediate pyrimidine derivatives, 2,5‐diamino‐4‐(2,3‐dihydroxypropylamino)‐6‐chloropyrimidine (5a) and 2,5‐diamino‐4‐(4‐hydroxybutylamino)‐6‐chloropyrimidine (5b) are novel.
A new synthetic approach to the C‐D ring portion of streptonigrin analogues
Authors: Kilama John J. , Iyengar Bhashyam S. , Remers William A. , Mash Eugene A.
Published: May 2009

Development of an efficient synthesis of the C‐D ring portion of streptonigrin is a key operation in the synthesis of this antibiotic and its analogues. A new method for the synthesis of 3‐cyano‐5,6‐dimethyl‐4‐(3,4,5‐trimethoxyphenyl)‐2‐pyridone (14), a compound having the requisite functionality for conversion into a streptonigrin analogue, has been established. It involves treatment of 3,4,5‐trimethoxybenzonitrile with ethylmagnesium bromide and malononitrile to give propylenemalononitrile derivative 7, which is condensed with trimethyl orthoacetate to give a mixture of 9 and pyridine derivative 12. Demethylation of 12 then affords 14. The overall yield for this route was 50%, allowing for conversion of 9 to 12.
Dimroth‐rearranged products in the reactions of 1‐aryl‐2‐methylthiopyrimidinium salts with hydrazines
Authors: Liebscher Jürgen , Hassoun Ahmed , van der Plas Henk , Stam C.
Published: May 2009

Reaction of 1‐aryl‐2‐methylthiopyrimidinium salts with hydrazine does not lead to substitution at C‐2 but to rearrangement into 1,2‐diaminopyrimidinium salts. An ANRORC‐mechanism involving an azatriene as intermediate is proposed.
Synthesis of novel cyclic sulfone dihydropyridines facilitated by a selective ethyl diazoacetate ring expansion
Authors: Dodd John H. , Schwender Charles F. , Gray‐Nunez Yolanda
Published: May 2009

A series of novel cyclic sulfone dihydropyridines with five to nine membered rings have been synthesized. Anomalous intermediates isolated from the Hantzch condensation were found to vary depending on the sulfone ring size and aromatic substitution. Tin tetrachloride has been shown to be a superior Lewis acid catalyst for ethyl diazoacetate ring expansion of the requesite β‐keto cyclic sulfone precursors.
Double 1,3‐dipolar cycloadditions of meso‐ionic heterocycles with N‐phenylmaleimide
Authors: Nan'ya Seiko , Goto Shinya , Butsugan Yasuo
Published: May 2009

3‐Phenylsydnone and 2,4‐diphenyl‐3‐methyloxazolium 5‐oxide undergo double 1,3‐dipolar cycloadditions with two molecules of N‐phenylmaleimide to produce 4,8‐iminobenzo[1,2‐c:4,5‐c′]dipyrrole‐1,3,5,7‐tetrone derivatives in a stereoselective manner.
Synthesis of bis‐2,7‐substituted 1,2,3,6,7,8‐hexahydroisoindolo[5,6‐f]isoindole‐1,3,6,8‐tetraones
Authors: Boykin D. W. , Nowak‐Wydra Barbara , Baumstark A. L.
Published: May 2009

A series of bis‐2,7‐substituted 1,2,3,6,7,8‐hexahydroisoindolo[5,6‐f]isoindole‐1,3,6,8‐tetraones (naphthalene diimides) has been synthesized. The key intermediate required for synthesis of the naphthalene diimides, 2,3,6,7‐naphthalnetetracarboxylic dianhydride (2) was prepared starting from allene and maleic anhydride. The bis‐anhydride 2 was converted to the naphthalene diimides using conventional methodology by the reaction with amines in organic solvents.
Some new aspects related to the synthesis of meso‐substituted porphyrins
Authors: Gonsalves A. M. d'A Rocha , Varejão Jorge M. T. B. , Pereira Mariette M.
Published: May 2009

A general analysis of the steps of the Rothemund reaction, allowed for a better understanding and a significant improvement of this reaction as a synthetic method in some of the previously known difficult syntheses.
The synthesis of novel polycyclic heterocyclic ring systems via photocyclization. 5. [1]Benzothieno[2,3‐c]naphtho[2,1‐f]‐quinoline and [1]benzothieno[2,3‐c]naphtho[1,2‐g]quinoline
Authors: Luo Jiann‐Kuan , Castle Raymond N.
Published: May 2009

Two previously unknown heterocyclic ring systems, namely, [1]benzothieno[2,3‐c]naphtho[2,1‐f]quinoline (4) and [1]benzothieno[2,3‐c]naphtho[1,2‐g]quinoline (5) were synthesized via photocyclization of 3‐chloro‐N‐(2‐phenanthryl)benzo[b]thiophene‐2‐carboxamide (8) followed by chlorination and dechlorination. The total assignment of their 1H‐ and 13C‐nmr spectra was determined by utilizing inverse‐detected HMQC and HMBC two‐dimensional nmr spectroscopic methods.
Fused s‐triazino heterocycles. XVIII. 1,3,4,7,11c‐Pentaazabenz[de]anthracene and 1,3,4,6,7,11c‐hexaazabenz[de]anthracene. Two new ring systems
Authors: Shaw John T. , Thomas Robert J. , Herold Sherry A. , Gfesser Gregory A. , Isovitsch Ralph A.
Published: May 2009

The reaction of 2‐amino‐4‐chloro‐6‐methylpyrimidine (3a) with trimethylacetyl chloride gave 4‐chloro‐6‐methyl‐2‐trimethylacetamidopyrimidine (5). This latter compound with excess anthranilonitrile gave in one step 2‐t‐butyl‐5‐methyl‐1,3,4,7,11c‐pentaazabenz[de]anthracene (6a). To prepare 2‐t‐butyl‐5‐dimethylamino‐1,3,4,6,7,11c‐hexaazabenz[de]anthracene (6b) it was found necessary to first react 2‐amino‐4‐chloro‐6‐dimethylamino‐5‐triazine (3b) with anthranilonitrile to yield the intermediate product 2‐amino‐4(2‐cyanoanilino)‐6‐dimethylamino‐s‐triazine (4). Reaction of the latter with trimethylacetyl chloride gave 6b.
Studies on the constituents of bocconia cordata. IV. Transformation of sanguinarine into bocconine
Authors: Konda Yaeko , Urano Mieko , Harigaya Yoshihiro , Onda Masayuki
Published: May 2009

Nitration of ethoxysanguinarine with equimolar potassium nitrate and sulfuric acid, followed by treatment with sodium hydroxide and methanol, gives 10‐nitromethoxysanguinarine. Successive hydrogenation, diazotization and methanolysis convert 10‐nitromethoxysanguinarine into bocconine.
Heterocycles. XXVI. A total synthesis of optically pure (+)‐catechin pentaacetate
Authors: Urano Mieko , Kagawa Hitoshi , Harigaya Yoshihiro , Li Shaoshun , Onda Masayuki
Published: May 2009

A total synthesis of optically pure (+)‐catechin pentaacetate has been established using the (‐)‐chalcon epoxide (100% ee) derived from 3,4,2′,4′,6′‐pentakis(methoxymethoxy)chalcon as the starting material. The optical purity of the product is confirmed by 1H nmr analysis in the presence of a shift reagent.
A facile synthesis of pyrazole‐5‐sulfonamide derivatives
Authors: Yamamoto Susumu , Sato Toshiaki , Morimoto Katsushi , Makino Kenzi
Published: May 2009

The reaction of the 5‐unsubstituted pyrazoles 2a‐k with lithium diisopropylamide or n‐butyllithium gave intermediary 5‐lithiopyrazoles, whose reaction with sulfur dioxide afforded the lithium pyrazole‐5‐sulfinates 3a‐k. Subsequent reaction of 3a‐k with N‐chlorosuccinimide followed by ammonolysis provided the pyrazole‐5‐sulfonamides 5a‐k.
Reactions 1‐acetyl‐3‐oxo‐2,3‐dihydroindole with alkyl 2‐cyano‐3‐alkoxypropenoate and alkyl 2‐alkoxycarbonyl‐3‐alkoxy‐propenoate. Synthesis of 9‐acetoxypyrrolo[1,2‐a]indol‐3‐one derivatives
Authors: Mérour J. Y. , Piroëlle S.
Published: May 2009

1‐Acetyl‐3‐oxo‐2,3‐dihydroindole reacted with methyl 2‐cyano‐3‐methoxypropenoate and ethyl 2‐cyano‐3‐ethoxypropenoate in the presence of sodium hydride, affording compounds 3 (2‐(2‐cyano‐2‐alkoxycarbonyl‐vinyl)‐3‐hydroxyindole). Methyl 2‐methoxycarbonyl‐3‐methoxypropenoate gave compounds 4 or compounds 5 (in the presence of Triton B). Heating compounds 3 or their acetylated derivatives in acetic anhydride at reflux afforded 9‐acetoxy‐(3H)‐pyrrolo[1,2‐a]indol‐3‐one 8.
Reactions of 3‐oxo‐2,3‐dihydrobenzofuran with alkyl 2‐cyano‐3‐alkoxypropenoate and alkyl 2‐alkoxycarbonyl‐3‐alkoxypropenoate. Synthesis of pyran derivatives
Authors: Mérour J. Y. , Cossais F.
Published: May 2009

3‐Oxo‐2,3‐dihydrobenzofuran reacted with ethyl 2‐cyano‐3‐ethoxypropenoate, methyl 2‐cyano‐3‐methoxy‐propenoate affording compounds 3 (2‐(2‐cyano‐2‐alkoxycarbonylvinyl)‐3‐hydroxybenzofuran) obtained as a mixture of Z + E isomers. Methyl 2‐methoxycarbonyl‐3‐methoxypropenoate gave compound 4. Malonic compounds added on 2‐dimethylaminomethylene‐3‐oxo‐2,3‐dihydrobenzofuran 6 for giving compound 3 or 2‐oxo‐3‐methoxycarbonyl‐2H‐pyrano[3,2‐b]benzofuran 8. Compound 8 was also obtained by heating compound 4 in xylene.
Réarrangement de thiénobenzothiépinones en thiénoisothiazolinone et benzoisothiazolinone
Authors: Daich Abdelali , Decroix Bernard
Published: May 2009

Dans les conditions de la réaction de Schmidt les thiénobenzothiépinones 1, 2 et 13 subissent un réarrangement respectivement en N‐benzylthiéno[2,3‐d]isothiazolin‐3‐one (5) et benzoisothiazolin‐3‐one (6). Un mécanisme de ce réarrangement est proposé.
Pyrimidine derivatives. VI. Synthesis of mono‐, di‐, tri‐, and tetrabromo‐substituted pyrimidine derivatives
Authors: Kinoshita Toshio , Okunaka Tomoko , Ohwada Takehiro , Kawanaka Hiroyuki , Furukawa Sunao
Published: May 2009

The following bromo‐2,4(1H,3H)‐pyrimidinediones possessing a bromo substituent at the 5‐position and side chains at the 1‐ and 6‐positions were prepared. The three types of mono‐bromo derivatives are: 1‐(bromoalkyl)‐3,6‐dimethyl‐ 3a‐d, 5‐bromo‐3,6‐dimethyl‐1‐(hydroxyalkyl)‐ 4a‐d, and 1‐(acetoxyalkyl)‐5‐bromo‐3,6‐dimethyl‐2,4(1H,3H)‐pyrimidinediones 11a‐d. The three types of dibromo derivatives are: 5‐bromo‐1‐(bromoalkyl)‐3,6‐dimethyl‐ Sa‐d, 1‐(acetoxyalkyl)‐5‐bromo‐6‐bromomethyl‐ 8a, 8c, and 8d, and 5‐bromo‐6‐bromomethyl 1‐(hydroxyalkyl)‐2,4(1H,3H)‐pyrimidinediones 9a, 9c, and 9d. Likewise one group of tribromo and one group of tetrabromo derivatives are: 5‐bromo‐1‐(bromoalkyl)‐6‐bromomethyl‐7a‐d and 5‐bromo‐1‐(bromoalkyl)‐6‐dibromomethyl‐2,4(1H,3H)‐pyrimidinediones 6a‐d.
A convenient route to diazepines by intramolecular cyclisation of carbonylazides
Authors: Daich Abdelali , Povazanec Frantisek , Decroix Bernard
Published: May 2009

The appropriate substituted carbonylazides I treated with warm acetic acid give the corresponding acetamide IV or the cyclic lactam VI. This is a convenient route to 10,11‐Dihydro‐5H‐pyrrolo[1,2‐a][1,4]‐benzodiazepin‐11‐one and 10,11‐Dihydro‐4H‐thieno[2,3‐e]pyrrolo[1,2‐a][1,4]diazepin‐10‐one.
Synthesis and properties of 5‐(1,2‐dihaloethyl)‐2′‐deoxyuridines and related analogues
Authors: Kumar Rakesh , Knaus Edward E. , Wiebe Leonard I.
Published: May 2009

The regiospecific reaction of 5‐vinyl‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridine (2) with HOX (X = Cl, Br, I) yielded the corresponding 5‐(1‐hydroxy‐2‐haloethyl)‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridines 3a‐c. Alternatively, reaction of 2 with iodine monochloride in aqueous acetonitrile also afforded 5‐(1‐hydroxy‐2‐iodoethyl)‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridine (3c). Treatment of 5‐(1‐hydroxy‐2‐chloroethyl)‐ (3a) and 5‐(1‐hydroxy‐2‐bromoethyl)‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridine (3b) with DAST (Et2NSF3) in methylene chloride at ‐40° gave the respective 5‐(1‐fluoro‐2‐chloroethyl)‐ (6a, 74%) and 5‐(1‐fluoro‐2‐bromoethyl)‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridine (6b, 65%). In contrast, 5‐(1‐fluoro‐2‐iodoethyl)‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridine (6e) could not be isolated due to its facile reaction with methanol, ethanol or water to yield the corresponding 5‐(1‐methoxy‐2‐iodoethyl)‐ (6c), 5‐(1‐ethoxy‐2‐iodoethyl)‐ (6d) and 5‐(1‐hydroxy‐2‐iodoethyl)‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridine (3c). Treatment of 5‐(1‐hydroxy‐2‐chloroethyl)‐ (3a) and 5‐(1‐hydroxy‐2‐bromoethyl)‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridine (3b) with thionyl chloride yielded the respective 5‐(1,2‐dichloroethyl)‐ (6f, 85%) and 5‐(1‐chloro‐2‐bromoethyl)‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridine (6g, 50%), whereas a similar reaction employing the 5‐(1‐hydroxy‐2‐iodoethyl)‐ compound 3c afforded 5‐(1‐methoxy‐2‐iodoethyl)‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridine (6c), possibly via the unstable 5‐(1‐chloro‐2‐iodoethyl)‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridine intermediate 6h. The 5‐(1‐bromo‐2‐chloroethyl)‐ (6i) and 5‐(1,2‐dibromoethyl)‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridine (6j) could not be isolated due to their facile conversion to the corresponding 5‐(1‐ethoxy‐2‐chloroethyl)‐ (6k) and 5‐(1‐ethoxy‐2‐bromoethyl)‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridine (61). Reaction of 5‐(1‐hydroxy‐2‐bromoethyl)‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridine (3b) with methanolic ammonia, to remove the 3′,5′‐di‐O‐acetyl groups, gave 2,3‐dihydro‐3‐hydroxy‐5‐(2′‐deoxy‐β‐D‐ribofuranosyl)‐furano[2,3‐d]pyrimidine‐6(5H)‐one (8). In contrast, a similar reaction of 5‐(1‐fluoro‐2‐chloroethyl)‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridine (6a) yielded (E)‐5‐(2‐chlorovinyl)‐2′‐deoxyuridine (1b, 23%) and 5‐(2′‐deoxy‐β‐D‐ribofuranosyl)furano[2,3‐d]pyrimidin‐6(5H)‐one (9, 13%). The mechanisms of the substitution and elimination reactions observed for these 5‐(1,2‐dihaloethyl)‐3′,5′‐di‐O‐acetyl‐2′‐deoxyuridines are described.
A phenolic glycoside from artemisia sacrorum
Authors: Konda Yaeko , Funato Nobuyuki , Harigaya Yoshihiro , Li Xian , Zhang Dezhi , Onda Masayuki
Published: May 2009

A phenolic glycoside has been isolated from Artemisia sacrorum grown in the Northeast of China. This compound is identified to be 4‐O‐β‐D‐glucopyranosyl‐2‐O‐methylphloroacetophenone by means of nmr spectroscopy and synthesis.
Novel heterocyclization of 4‐phenylthiosemicarbazones and related compounds with chlorocarbonylsulfenyl chloride
Authors: Kabashima Shigeru , Okawara Tadashi , Yamasaki Tetsuo , Furukawa Mitsuru
Published: May 2009

Chlorocarbonylsulfenyl chloride was allowed to react with 1‐alkylidene‐4‐phenylthiosemicarbazones in the presence of triethylamine to give 1,2,4‐triazolines, whereas with 1‐arylidene‐4‐phenylthiosemicarbazones to afford 1,2,4‐dithiazolidines. Treatment of diarylidenethiocarbohydrazides and diarylidenaminoguanidines with chlorocarbonylsulfenyl chloride under similar conditions gave 1,2,4‐dithiazolidines and 1,2,4‐thiadiazolidines, respectively.
Synthesis of 4‐hydroxy‐3‐triftuoromethylpyrazoles
Authors: Iwata Satoru , Namekata Junji , Tanaka Kiyoshi , Mitsuhashi Keiryo
Published: May 2009

Trifluoroacetaldehyde hydrazones are condensed with glyoxals to give 4‐hydroxy‐3‐trifluoromethylpyrazoles, the reaction offering a novel route to 4‐hydroxypyrazoles carrying trifluoromethyl group. The 4‐hydroxyl group was easily converted to its derivatives by the reaction with various electrophiles.
Inhibition of human dihydrofolate reductase by 2,4‐diaminoquinazolines bearing simple substituents on the aromatic ring
Authors: Hynes John B. , Tomažič Alenka , Kumar Arvind , Kumar Veena , Freisheim James H.
Published: May 2009

A series of thirty eight 2,4‐diaminoquinazolines having diverse substitution patterns on the aromatic ring was evaluated for inhibitory activity against dihydrofolate reductase (DHFR) obtained from a human lymphoblast cell line. Many of these compounds were also evaluated as inhibitors of rat liver DHFR under the same experimental conditions. In most instances the results obtained with each enzyme were comparable indicating that the rodent enzyme is a suitable model for the human DHFR as far as the determination of I50 values is concerned. The results demonstrate that relatively simple 5‐substituted‐ or 5,6‐disubstituted‐2,4‐diaminoquinazolines can be potent DHFR inhibitors. The presence of a nonpolar substituent at position 7 or 8 was highly detrimental to inhibitory potency.
The fragmentation behavior of differently substituted 2‐amino‐1,3,4‐benzotriazepines
Authors: Vainiotalo P. , Ottoila P. , Morgenstern O. , Richter P.
Published: May 2009

The mass spectra of eighteen 2‐amino‐1,3,4‐benzotriazepines were recorded under electron ionization, and the fragmentation patterns were elucidated by metastable ion analysis and exact mass measurements. The most typical fragmentations were ring contraction reactions with the loss of nitrogen atoms at positions 3 and 4. Extensive rearrangement reactions took place as well. In these the substituted 2‐amino group played an important role. Isomeric compounds were easily distinguished.
Ground state vs. transition state substituent effects on reactions of aziridinium salts
Authors: Crist Delanson R. , Turujman Saleh A. , Hashmall Joseph A.
Published: May 2009

The possibility that the similarity of Hammett ρ values for several very different reactions of 2‐arylaziridinium salts is due to ground state effects was investigated by MO methods and ESCA. Minimum energy structures of p‐nitrophenyl‐, phenyl‐, and p‐methoxyphenyl‐substituted ions, however, have the same C2N bond lengths. This result shows that substituent effects are primarily a transition state phenomenon, even in the three‐membered ring heterocycles. In agreement, the ground state does not have significant amino carbocation character based on similar charge distributions of 2‐phenyl‐N,N‐dimethylaziridinium ion and N,N,N‐trimethylbenzylammonium ion as well as the same nitrogen ls binding energies by ESCA studies on corresponding salts.
The synthesis of novel polycyclic heterocyclic ring systems via photocyclization. 6. Naphthothienonaphthyridines
Authors: Castle Raymond N. , Pakray Sudabeh , Martin Gary E.
Published: May 2009

Five novel polycyclic heterocyclic ring systems are reported via photocyclization. The specific final products in these ring systems are: naphtho[1′,2′:4,5]thieno[2,3‐c][1,8]naphthyridin‐6(5H)‐one (5), naphtho‐[1′,2′:4,5]thieno[2,3‐c][1,6]naphthyridin‐6(5H)‐one (6), naphtho[1′,2′:4,5]thieno[2,3‐c]‐1,5‐naphthyridine (9), naphtho[1′,2′:4,5]thieno[2,3‐c][1,2,4]triazolo[4,3‐a]‐1,5‐naphthyridine (12), and naphtho[2′,1′:4,5]thieno[2,3‐c]‐1,5‐naphthyridine (17). The direction of photocyclization to produce 9 was established from a zero quantum two‐dimensional nmr spectroscopy experiment (ZQCOSY) using 6‐chloronaphtho[1′,2′:4,5]thieno[2,3‐c]‐1,5‐naphthyridine (8) as the model compound.
A convenient synthesis of (2‐styrylchromon‐8‐yl)acetic acids
Authors: Zammattio F. , Brion J. D. , Belachmi L. , Le Baut G.
Published: May 2009

(2‐Styrylchromon‐8‐yl)acetic acids, structural analogs of (flavon‐8‐yl)acetic acid (FAA) have been synthesized with satisfactory yields according to two different methods. The 1H and 13C nmr data fovor the S‐trans stereoisomers.
Synthesis of 2‐guanyl‐4‐(3‐substituted‐phenyl)thiazoles with potent histamine H2‐antagonism activity
Authors: Santilli Arthur A. , Scotese Anthony C. , Morris Robert L. , Bell Stanley C.
Published: May 2009

The syntheses of novel 2‐guanyl‐4‐(3‐substituted‐phenyl)thiazoles showing potent histamine H2‐antagonism activity is reported. The most potent compound is 17 where the substitution at the 3‐position of the phenyl ring is an N‐methylamidino function.
Synthesis of 6,6‐disubstituted penems
Authors: Rossi Tino , Andreotti Daniele , Tamburini Bruno , Marchioro Carla
Published: May 2009

The synthesis of a series of 6,6‐disubstituted penems starting from penicillanate 5a is described. These penems were isolated and characterized as their pivaloyloxy methyl ester.
Synthesis of 2H‐pyrazolo[3,4‐b]pyridin‐3‐oles via cyclization of pyrazolacrylonitriles
Authors: Cocco Maria Teresa , Congiu Cenzo , Onnis Valentina
Published: May 2009

The reaction of 1‐acyl‐3‐amino‐5‐pyrazolones 1 with ethyl ethoxymethylenecyanoacetate and ethoxymethylenemalononitrile 2 is described. Thermal cyclization in phenyl ether of the obtained pyrazol‐acrylonitriles 3 provides good yields of pyrazolopyridin‐3‐ol derivatives 4.
Synthesis of 5′‐azido‐ and 5′‐amino‐2′,5′‐dideoxynucleosides from quinazoline‐2,4(1H,3H)‐diones
Authors: El‐Barbary Ahmed A. , El‐Brollosy Nasser R. , Pedersen Erik B. , Nielsen Claus
Published: May 2009

Quinazoline‐2,4(1H,3H)‐diones 4 were silylated and condensed with methyl 5‐azido‐2,5‐dideoxy‐3‐O‐(4‐methylbenzoyl)‐α,β‐D‐erythro‐pentofuranoside (3) using trimethylsilyl trifluoromethanesulfonate (TMS triflate) as the catalyst to afford the corresponding 5′‐azidonucleosides 5. 1‐(5‐Azido‐2,5‐dideoxy‐α‐D‐erythro‐pentofuranosyl)quinazoline‐2,4(1H,3H)‐diones 6 and the corresponding β anomers were obtained by treating 5 with sodium methoxide in methanol at room temperature. 6‐Methyl‐1‐(5‐amino‐2,5‐dideoxy‐β‐D‐erythro‐pentofuranosyl)quinazoline‐2,4(1H,3H)‐dione (8) was obtained by treatment of the corresponding azido derivative 7 with triphenylphosphine in pyridine, followed by hydrolysis with ammonium hydroxide.
Intramolecular photocycloadditions of 6,6′‐dimethyl‐4,4′‐polymethylenedioxy‐di‐2‐pyrones
Authors: Shimo Tetsuro , Ueda Shinichi , Suishu Takaaki , Somekawa Kenichi
Published: May 2009

Photosensitized reactions of 4,4′‐polymethylene‐di‐2‐pyrones 2b‐e afforded [2+2]‐cycloadducts 3‐5, site‐selectively. The selectivity depended upon the methylene chain length. Namely, the three carbon chain gave a syn head‐to‐head adduct 3b at the 3,4‐position of the 2‐pyrone ring, the four to six carbon chains gave syn head‐to‐head adducts 4c‐e at the 5,6‐position and/or anti head‐to‐head adducts 5d,e at the 5,6‐position, respectively. The intramolecular cycloaddition mechanism was also explained from results calculated by means of PM3‐CI method.
Haloacetylated enol ethers. 5 [5]. Heterocyclic ring closure reactions of β‐alkoxyvinyl dichloromethyl ketones with hydroxylamine
Authors: Martins Marcos A. P. , Zoch Alana N. , Flores Alex F. C. , Clar Günter , Zanatta Nilo , Bonacorso Helio G.
Published: May 2009

The β‐alkoxyvinyl dichloromethyl ketones 1a‐d are cyclocondensed with hydroxylamine hydrochloride in pyridine to afford the 5‐hydroxy‐5‐dichloromethyl‐4,5‐dihydroisoxazoles 2a‐d in good yield. The cyclo‐condensation of compound 1c gave, together with 2c, 3‐cyano‐2‐hydroxy‐2‐dichloromethyltetrahydrofuran 5c. The dehydratation of compounds 2a,b, derived from acyclic enol ethers, with concentrated sulfuric acid at 30°, led the corresponding 5‐dichloromethylisoxazoles 3a,b. The dehydratation of compounds 2c,d, derived from cyclic enol ethers, with concentrated sulfuric acid at 30°, led the bicyclic 4,5‐dihydroisoxazoles 4c,d, and at 55°, a competitive rearrangement reaction gives the 3‐cyano‐2‐hydroxy‐2‐dichloromethyl‐2H‐pyran 5d.
Photochemical behavior of some substituted benzophenoxazinones
Authors: Barone Vincenzo , Bolognese Adele , Buonanno Marina
Published: May 2009

Irradiation of some substituted benzophenoxazinones in methanol solution by visible light yields dimerization and substitution products. A possible radical mechanism is proposed and validated by quantum mechanical computations.
Synthesis of the cardiotonic bemarinone, 5,6‐dimethoxy‐4‐methyl‐2(1H)‐quinazolinone, utilizing a directed metalation approach
Authors: Conley Richard A. , Barton Donald L. , Stefanick Stephen M. , Lam Margaret M. , Lindabery Gregory C. , Kasulanis Charles F. , Cesco‐Cancian Sergio , Currey Stephen , Fabian Arthur C. , Levine Seymour D.
Published: May 2009

Several methods for the synthesis of bemarinone, 5,6‐dimethoxy‐4‐methyl‐2(1H)‐quinazolinone, were explored with the most successful being a directed metalation route. Details of the lithiation and the subsequent reaction with electrophiles of 3′,4′‐dimethoxy‐2,2‐dimethylpropioanilide and other derivatives of 3,4‐dimethoxyaniline are given.
Pyridine‐substituted hydroxythiophenes. V. Preparation of 5‐(2‐, 3‐and 4‐pyridyl)‐2‐hydroxythiophenes
Authors: Zhang Yihua , Hömfeldt Anna‐Britta , Gronowitz Salo
Published: May 2009

5‐(2‐, 3‐ and 4‐Pyridyl)‐2‐t‐butoxythiophenes have been prepared in very good yields by Pd(0) catalyzed cross‐coupling of the three isomeric bromopyridines with 5‐trimethylstannyl‐2‐t‐butoxythiophene derived from 2‐bromothiophene via 2‐t‐butoxythiophene. Dealkylation of 5‐(2‐, 3‐ and 4‐pyridyl)‐2‐t‐but‐oxythiophenes with boron trifluoride etherate in dichloromethane at room temperature led to predominant formation of rearranged products, 5‐(2‐ and 3‐pyridyl)‐3‐t‐butyl‐3‐thiolene‐2‐ones, together with a small amount of 5‐(2‐ and 3‐pyridyl)‐2‐hydroxythiophenes as a mixture of two tautomeric keto forms in the case of the 2‐pyridyl and the 3‐pyridyl isomers, and exclusive formation of rearranged product in the case of the 4‐pyridyl isomer.

However, dealkylation of 2‐methoxy‐5‐(2‐, 3‐ and 4‐pyridyl)thiophenes, prepared similarly to the 5‐(2‐, 3‐ and 4‐pyridyl)‐2‐t‐butoxythiophenes, with boron tribromide under the same reaction conditions as above resulted exclusively in the tautomeric mixture of 5‐(2‐ and 3‐pyridyl)‐3‐thiolene‐2‐ones and 5‐(2‐ and 3‐pyridyl)‐4‐thiolene‐2‐ones in the case of the 2‐pyridyl and 3‐pyridyl isomers. In the case of the 4‐pyridyl isomer polymerization took place.
The preparation of intercalating isoxazoles via a nitrile oxide cycloaddition
Authors: Mosher Michael D. , Natale Nicholas R.
Published: May 2009

Pyridinium chlorochromate oxidation of 9‐methylacridine (2) affords the corresponding aldehyde 3 in good yield. Conversion of the aldehyde to the hydroximinoyl chloride 5a was accomplished via reaction of the corresponding oxime with N‐chlorosuccinimide. Dipolar addition to the enamine of ethylacetoacetate provided the corresponding isoxazoles 1 in good yield.
Synthesis of 1,2,3‐triazolo[1,5‐a]pyridine ester derivatives
Authors: Latham Elliot J. , Stanforth Stephen P.
Published: May 2009

Lithiation of 1,2,3‐triazolo[1,5‐a]pyridines 4b and 4c with lithium diisopropylamide (LDA) gave the corresponding lithio derivatives 5b and 5c from which esters 6b and 6c were obtained by treatment with carbon dioxide and then dimethyl sulfate. Lithio derivatives 5a‐5c reacted with DMF giving aldehydes 7a‐7c. Esters 9a‐9c were prepared from aldehydes 7a‐7c and carbomethoxymethylenetriphenylphosphorane.
Synthesis of pyrido[3,4‐d] benzazepines
Authors: Kunick Conrad , Link Andreas
Published: May 2009

The synthesis of some derivatives of the novel heterocyclic ring system pyrido[3,4‐d][1]benzazepine is reported. Thus, pyrido[3,4‐d][1]benzazepin‐7‐one 6 was prepared by cyclisation of the Michael adduct 5 with ammonium ferric sulfate. Reaction of 6 with phosphorus pentasulfide gave the thiolactam 7, which after methylation and subsequent reaction with amines furnished the amidines 10.
Synthesis of some oxadiazole derivatives of d‐mannose
Authors: Fascio Mirta L. , D'Accorso Norma B.
Published: May 2009

The syntheses of 2‐methyl‐5‐[1′,2′,3′,4′,5′‐penta‐O‐benzoyl‐D‐manno‐pentitol‐1′‐yl]‐1,3,4‐oxadiazole and 5‐methyl‐3‐[1′,2′,3′,4′,5′‐penta‐O‐benzoyl‐D‐manno‐pentitol‐1‐′yl]‐1,2,4‐oxadiazole, as well as their intermediate products, are described. Their 1H and 13C nmr and ms spectra are presented and their preferential conformation in solution are proposed.
Synthesis of 8,9‐dihydrodipyrazolo[3,4‐b:4′,3′‐f][1,5]diazocin‐10(1H)‐one. A new ring system
Authors: Migliara Onofrio , Lamartina Liliana , Timoneri Marina , Plescia Salvatore
Published: May 2009

8,9‐Dihydrodipyrazolo[3,4‐b:4′,3′‐f][1,5]diazocin‐10(1H)‐ones 7 were prepared by cyclization of 1‐ethyl‐N,3‐dimethyl‐4‐acetamido‐N‐(1‐R1‐3‐R2‐1H‐pyrazol‐5‐yl)‐1H‐pyrazole‐5‐carboxamides 6 by a Bischler‐Napieralski cyclization. A complete assignment of the chemical shifts to the carbon atoms of compound 7 was performed by different nmr experiments, such as DEPT and XHDEPT for onebond CH correlations and COLOC experiments for long‐range C‐H correlations.
Synthesis of 3H‐thieno[3,2‐c]‐1,2‐dithiole‐3‐thione and its reaction with n‐butylamine
Authors: Pregnolato Massimo , Borgna Pietro , Terreni Marco
Published: May 2009

A convenient synthesis of 3H‐thieno[3,2‐c]‐1,2‐dithiole‐3‐thione (7) is proposed. The reaction of 7 with n‐butylamine afforded the N‐butylthieno[3,2‐c]isothiazole‐3(2H)‐thione (7a) in dynamically equilibrium [1] with its 3H‐thieno[3,2‐c]‐1,2‐dithiole‐N‐butyl‐3‐imino isomer 7b. Characterizations and antimicrobial activities of the synthesized products are reported.
Synthesis of trans‐7‐hydroxymethyl‐2‐(2‐benz[d]isoxazol‐3‐yl)octahydro‐2H‐pyrido[1,2‐a]pyrazine
Authors: Urban Frank J.
Published: May 2009

An efficient synthesis of trans‐7‐hydroxymethyl‐2‐(2‐benz[d]isoxazol‐3‐yl)octahydro‐2H‐pyrido[1,2‐a]‐pyrazine 2 is presented which relies on the equilibration of cis‐dimethyl piperidinedicarboxylate followed by alkylation with phthalimidoethyl triflate.
On the syntheses of 8‐Heteroaryl‐substituted 9‐(β‐D‐Ribofuranosyl)‐2,6‐diaminopurines through Pd‐catalyzed coupling in the presence of cupric oxide
Authors: Ozola Vita , Persson Tina , Gronowitz Salo , Hörnfeldt Anna‐Britta
Published: May 2009

Convenient methods for the preparation of 9‐(β‐D‐ribofuranosyl) derivatives of 8‐(2‐ and 3‐thienyl)‐2,6‐diaminopurine and of 8‐(2‐ and 3‐furyl)‐2,6‐diaminopurine, which are potential antiviral agents has been worked out. The key step was a Pd(0)‐catalyzed Stille coupling between 2‐ and 3‐tributylstannylthiophene and 2‐ and 3‐tributylstannylfuran and trimethylsilyl protected 9‐(β‐D‐ribofuranosyl)‐2,6‐diamino‐8‐bro‐mopurine. The use of N,N‐dimethylformamide as solvent at 110° and dichloro(diphenylphosphine‐propane)palladium(II) [PdC12(dppp)] with cupric oxide as co‐reagent was essential in order to obtain a fast reaction and high yields.
A short synthesis of C‐glycosyl pyrazoles and pyrroles
Authors: Del Valle José L. , Polo Cecilia , Torroba TomÁS , Marcaccini Stefano
Published: May 2009

The sodium salt of TOSMIC reacted with (E)‐3,4,5,6,7‐penta‐O‐acetyl‐1,2‐dideoxy‐1‐C‐nitro‐D‐galacto‐ (1) and ‐D‐manno‐hept‐1‐enitol (2) to give 3‐(D‐galacto‐ (3) and 3‐(D‐manno‐penta‐O‐acetylpentitol‐1‐yl)‐4‐nitropyrrole (4), respectively. Compound 1 reacted with diaryl nitrile imines, affording 1,3‐diaryl‐4‐(1,2,3,4,5‐penta‐O‐acetyl‐D‐galacto‐pentitol‐1‐yl)pyrazoles 5 and 6.
Synthesis of aryl 2‐(2‐imidazolyl)ethyl ketones
Authors: Abdelaal Salma M. , Kim Jang‐Woo , Bauer Ludwig
Published: May 2009

The Claisen‐Schmidt condensation of 1‐(triphenylmethyl)‐2‐imidazolecarboxaldehyde with acetophenones yielded 1‐aryl‐3‐[1‐(triphenylmethyl)‐2‐imidazolyl]propen‐1‐ones 7. Selective catalytic hydrogenation over platinum of 7 furnished 1‐aryl‐3‐(2‐imidazolyl)‐1‐propanones 8. An alternate synthesis of 8 started with sodium borohydride reduction of 7 to give allylic alcohols, 1‐aryl‐3‐[1‐(triphenylmethyl)‐2‐imidazolyl]‐2‐propen‐1‐ols 10, which were rearranged by hot aqueous sodium to 8. Acid hydrolysis of 8 provided the title compounds and triphenylmethanol.
Oxidation of 5‐hydroxymethylfurfural and derivatives to furanaldehydes with 2,2,6,6‐tetramethylpiperidine oxide radical ‐ co‐oxidant pairs
Authors: Cottier Louis , Descotes Gérard , Viollet Estelle , Lewkowski Jaroslaw , Skowroñski Romuald
Published: May 2009

The oxidation of 5‐hydroxymethylfurfural (1) or 5‐hydroxymethylfurfurylideneacetophenone (4) with various 4‐substituted 2,2,6,6‐tetramethylpiperidine radicals (TEMPO) 3a‐d and supporting co‐oxidants gave corresponding aldehydes 2 or 5 in fair yields.
Synthesis of cyclic and acyclic nucleoside analogues having a thiophene or dihydrothiophene ring fused to the d side of an uracil
Authors: Jourdan Fabrice , Renault Jacques , Karamat Abdesselam , Laduríe Daniel , Robba Max
Published: May 2009

Synthesis of cyclic and acyclic nucleosides was achieved by alkylation of various new aglycones following the Vorbrüggen and Niedballa's procedure [6]. The analytical results allowed us to conclude that the alkylation occured on N1 site and led to the β anomeric form for the cyclic nucleosides.
The synthesis and analgesic properties of new spiroisochromanyl acid derivatives synthesized from natural safrole
Authors: Cabral Lucio M. , Barreiro Eliezer J.
Published: May 2009

We describe in this paper the synthesis of a new spiro[2‐carboxycyclopentane‐1,1‐(6,7‐methylene‐dioxy)isochroman] and a spiro[2‐carboxycyclohexane‐1,1‐(6,7‐methylenedioxy)isochroman] acids 11 and 12, obtained from natural safrole (7), isolated from Sassafras oil. These derivatives were obtained in high overall yield using a synthetic route in which was observed brevity and appreciable diastereoselectivity in the intramolecular regioalkylation of the 6‐position of the aromatic system of the natural starting material, the key step of the synthetic route representing a variable in the well‐known Friedel‐Crafts reaction. The new acids, derivatives 11 and 12, were obtained in ca. 74% and 78% overall yield. They show a good analgesic profile in the pharmacological assay, the test in mice abdominal contortion.
Synthesis of small‐medium ring thioanhydrides
Authors: Kates Michael J. , Schauble J. Herman
Published: May 2009

Reaction of five‐membered ring anhydrides with sodium sulfide has previously been employed for synthesis of the corresponding thioanhydrides in low yields. Re‐examination of the stoichiometry reveals reaction of cyclic anhydride with sodium sulfide (2:1 respectively), affords the thioanhydride accompanied by the corresponding dicarboxylate in a 1:1 molar ratio. The mechanistic pathway for this reaction has also been elucidated. Optimization of reaction conditions has resulted in the synthesis of a variety of four to seven‐membered ring thioanhydrides in yields approaching theoretical.
Heterocycles from heterocycles. ‐ III[1]. 1,3,5‐trisubstituted hexahydro‐1,3,5‐triazines‐2‐ones from 1,3,5‐trisubstituted hexahydro‐1,3,5‐triazines and organic isocyanates
Authors: Verardo Giancarlo , Giumanini Angelo G. , Gorassini Fausto , Strazzolini Paolo , Benetollo Franco , Bombieri Gabriella
Published: May 2009

1,3,5‐Triscubstituted hexahydro‐1,3,5‐trazin‐2‐ones 3 are easily obtained by the reaction of 1,3,5‐trisub‐stituted hexahydro‐1,3,5‐triazines1with organic isocyanates2. The reaction is believed to occur by the sequential addition to2of two molecules of the monomericN‐methyleneamines in thermal equilibrium with 1. Substituent scrambling at the operating temperature (120°) was negligible. The crystal structure of 1,3,5‐triphenylhexahydro‐1,3,5‐triazin‐2‐one(3a)has been determined by X‐ray diffraction methods.
Synthesis of spiro[4′,5′,10,11‐tetrahydro‐5H‐dibenzo[a,d]cyclohepten‐5‐yl‐2′(3′H)‐furans] as potential cytokine inhibitors
Authors: Ting Pauline C. , Solomon Daniel M.
Published: May 2009

A synthesis of novel spiro[4′,5′,10,11‐tetrahydro‐5H‐dibenzo[a,d]cyclohepten‐5‐yl‐2′(3′H)‐furans] is described. The key reaction was formation of the tetrahydrofuran ring by cyclization of the diol 3 or the protected diol 10. These compounds were investigated as potential TNF‐α inhibitors.
Synthesis of 3‐amino‐2‐carbamoylthiophene and its reaction with cycloalkanones to form imines
Authors: Klemm L. H. , Wang Jun , Hawkins Lucas
Published: May 2009

3‐Amino‐2‐carbamoylthiophene (2) was obtained in 75% yield by reaction of methyl 3‐aminothiophene‐2‐carboxylate with saturated aqueous ammonia containing ammonium chloride catalyst at room temperature over a period of 2,3 months, Treatment of 2 with cyclopentanone, cyclohexanone, and cycloheptanone in ethanol at pH 3.4 gave facile formation of 2‐carbamoyl‐3‐cycloalkylidenaminothiophenes in yields of 73%, 86%, and 60%, respectively. Infrared and 1H nmr spectra of these imines indicate that they occur in intramolecularly hydrogenbonded form, i.e. with chelate rings. Comparison is made with reported syntheses and reactions of 2 and its isosteric 2‐aminobenzamide.
Synthetic routes to indenopyridine analogues of morphactins
Authors: Braven J. , Hanson R. W. , Smith N. G.
Published: May 2009

Investigation of a number of synthetic routes to aza analogues of Morphaetins led to the synthesis of (RS)‐methyl 5H‐5‐hydroxyindeno[1,2‐b]pyridine‐5‐carboxylate (6e) and the corresponding caboxamide. 6f.
Preparation and spectroscopic characterization of bis(6,8‐dimethoxychroman‐5‐yl)methanes
Authors: Rama Nasim H. , Saeed A. , Bird C. W. , Cobb J.
Published: May 2009

3,5‐Dimethoxyphenylalkan‐2‐ols react with diethoxymethane and boron trifluoride etherate, or aqueous formaldehyde and hydrochloric acid forming bis(6,8‐dimethoxychroman‐5‐yl)methanes.
Elucidation of the structure of quindolinone, a minor alkaloid of cryptolepis sanguinolenta: Submilligram 1H‐13c and 1H‐15N heteronuclear shift correlation experiments using micro inverse‐detection
Authors: Crouch Ronald C. , Davis Ann O. , Spitzer Timothy D. , Martin Gary E. , Sharaf Maged M. H. , Schiff Paul L. , Phoebe Charles H. , Tackie Albert N.
Published: May 2009

Elucidation of minor natural product structures has been significantly augmented by inverse‐detection; further improvement has been afforded by the development of micro inverse‐detection probes. We report here the elucidation of the structure of a new alkaloid, quindolinone (5H, 10H‐indolo[3,2‐b]quinolin‐11‐one), from the West African plant Cryptolepis sanguinolenta. All nmr data for this minor, preparative hplc‐isolated alkaloid, including 1H‐15N onebond heteronuclear shift correlation (HMQC) data, were recorded on an 800 μg sample of the alkaloid dissolved in 140 μl of 100% d6‐DMSO using a 400 MHz spectrometer.
Synthesis of new azonia‐helicenes with a quaternary nitrogen at the inner helix skeleton
Authors: Arai Sadao , Ishikura Masanori , Sato Kiyoshi , Yamagishi Takamichi
Published: May 2009

The 16c‐azonia[6]helicene salts, in which a carbon atom at the inner helix skeleton of [6]helicene is replaced by a quaternary nitrogen atom, have been synthesized by photo‐induced intramolecular quater‐nization of 2‐[2‐(1‐chloronaphthyl)vinyl]benzo[h]quinolines in acetonitrile.
Synthesis of 2,3,5,6‐tetrahydro‐4H‐1,4‐thiazin‐3‐one 1,1‐dioxides from methyl (styrylsulfonyl)acetate
Authors: Takahashi Masahiko , Yuda Junji
Published: May 2009

Methyl (styrylsulfonyl)acetate (1) was shown to be a useful building block for the synthesis of 5‐phenyl‐2,3,5,6–4H‐tetrahydro‐1,4‐thiazin‐3‐one (2), its 4‐amino 3, and 4‐hydroxy 4 derivatives. Their 2‐spirocyclopropanes 9, 10, and 11, and 2,7‐diphenyl‐6,7‐dihydro‐8H‐pyrimido[5,4‐b][1,4]thiazinc 5,5‐dioxide (18) were also prepared from 1.