摘要:

AbstractPhenolic cyclization of 2‐ethoxycarbonylmethylidenecyclohexanone (IV) with 3‐hydroxy‐4‐methoxyphenethylamine (V) were performed in the process of finding a synthetic approach to dihydroerysolidine (I). Thus, 16‐hydroxy‐15‐methoxyerythrinan‐6‐ene‐8‐one (VI) and 16‐hydroxy‐15‐methoxyerythrinan‐7‐ene‐8‐one (VII) were synthesized, both of which were hydrogenated in the presence of Adams platinum to give the same product (XI). Furthermore, on the basis of the mass spectra of XI and XII, these compounds were assumed to be stereoi

ISSN:0022-152X    

DOI:10.1002/jhet.5570060402

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

AbstractThe 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

ISSN:0022-152X    

DOI:10.1002/jhet.5570060403

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

Abstractα‐Methyl and α‐phenyl substituted 2 and 4‐styrylpyridines were prepared by classical routes. The geometrical isomers were separated and characterized on the basis of their U.V. absorption spectra and/or of their behaviour under U.V. irradiation which led to photoisomerization and photocyclization products. The last photoreaction, in the case of α‐phenyl derivatives, gave pyridyl‐substituted phenanthrenes and phenyl‐substituted azaphenanthrenes which were isolated and characterized.Spectral, chromatographic and physical properties oftransandcisderivatives and related photocyclization products are given as well as some kinetic data for the photochem

ISSN:0022-152X    

DOI:10.1002/jhet.5570060404

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

AbstractAn earlier method of preparation of γ‐hydroxyamides fromN‐substituted benzamides and ketones or aldehydes by means ofn‐butyllithium was improved and extended. The γ‐hydroxyamides were found to undergo cyclodehydration to form γ‐lactams with relatively strong acids, but cyclodeamination formed γ‐lactones with relatively weak acids; the γ‐lactams are substituted phthalimidines. The predominant course of cyclization was dependent also on the structure of the γ‐hydroxyamide. Certain γ‐hydroxyamides afforded phthalimidines with cold, concentrated sulfuric acid whereas certain others yielded γ‐lactones with this acid. The latter γ‐hydroxyamides, however, produced phthalimidines with the stronger acid, perchloric acid. The cyclodehydration reaction furnished a convenient and, apparently, quite general method for the synthesis of 2,3,3‐trisubstituted or 2,3‐disubstituted phthali

ISSN:0022-152X    

DOI:10.1002/jhet.5570060405

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

AbstractA study was made of the behavior of imidazole and six benzo‐N‐heterocyclic compounds upon direct treatment with anhydrous and hydrated hexafluoro‐ andsym‐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 reactingo‐phenylenediamine,o‐aminophenol, ando‐aminobenzenethiol with hexafluoroacetone hydrate, thus introducing the 2‐hydroxyhexafluoro‐2‐propyl moiety into the ringparato the amino group. A similar product was made fromo‐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 hete

ISSN:0022-152X    

DOI:10.1002/jhet.5570060406

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

AbstractCatalytic reductive scission of 4‐methylcinnoline (V) with Raney nickel affordedo‐amino‐β‐methylphenethylamine (IV) in 57% yield. Treatment of IV with carbon disulfide followed by thermal cyclization of the product furnished 1,3,4,5‐tetrahydro‐5‐methyl‐2H‐1,3‐benzodiazepine‐2‐thione (III). Reaction of III with ethyl chloroacetate, ethyl 2‐bromohexanoate, ethyl 2‐chloroacetoacetate, 2‐bromo‐2′‐methoxyacetophenone, and 2‐bromoacetophenone provided a series of substituted 5,6‐dihydro‐6‐methylthiazolo[2,3‐b][1,3]benzodiazepines. Condensation of III with 2‐chlorocyclopentanone and 2‐chlorocyclohexanone gave 2,3,10,11‐tetrahydro‐10‐methyl‐1H‐cyclopenta[4,5]thiazolo[2,3‐b][1,3]benzodiazepine and 7,8,9,10,12,13‐hexahydro‐13‐methylbenzothiazolo[2,3‐b][1,3]benzodiazepine, respectively. Structure assignments are disc

ISSN:0022-152X    

DOI:10.1002/jhet.5570060407

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

AbstractThe synthesis of variously substituted pyridazines by 1,4‐cycloaddition of cyclic enol ethers, esters, and some electron‐rich acetylenes is described. Extension of the scheme to include some imino‐ethers as dienophiles resulted in the synthesis of 1,2,4‐triazine deri

ISSN:0022-152X    

DOI:10.1002/jhet.5570060408

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

AbstractBy irradiation in methanol at 3000Å, aniline ando‐anisidine were produced from benzo‐triazole andN‐methylaniline andN‐methyl‐o‐anisidine were produced fromN‐methylbenzotriazole. Carbazole was the only product detected from similar treatment ofN‐phenylbenzotriazole. Linear naphthotriazole was photolytically transformed into β‐naphthylamine but a methoxy derivative could not be found. Angular naphthotriazole gave no identifiable photolytic product.u‐Triazolo[1,5‐α]pyridine underwent photolysis in methanol to give α‐picoline, α‐picolylmethyl ether and α‐picolylmethanol in low yield. A similar photolysis in acetic acid afforded α‐pyridylmethyl acetate. The mechanisms for the

ISSN:0022-152X    

DOI:10.1002/jhet.5570060409

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

AbstractMethods are described for the synthesis of 6,7‐dihydro‐5H‐pyrrolo[3,4‐d]pyrimidines having an aryl substituent in the 6‐position. 4‐Hydroxy‐, 4‐amino, 2‐amino‐4‐hydroxy and 2,4‐diamino derivatives were obtained. The synthetic route involved the preparation of 1‐aryl‐4‐cyano‐ or 4‐carboalkoxy‐3‐pyrrolidinones and 1‐aryl‐4‐cyano‐ or 4‐carboa

ISSN:0022-152X    

DOI:10.1002/jhet.5570060410

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY

摘要:

AbstractIn order to use the NMR spectra of dibenzothiophenes to determine the position of substitution, a series of compounds has been prepared, most of which are new while some represent an improved method of preparation of previously reported compounds. With the exception of one, the structures of the compounds prepared were not in doubt, however the splitting patterns and chemical shifts presented here will facilitate future structure determinations of dibenzothiophenes.

ISSN:0022-152X    

DOI:10.1002/jhet.5570060411

出版商:Wiley‐Blackwell    

年代:1969

数据来源: WILEY