摘要:

AbstractDie Umsetzung von 3.4‐Diazatricyclononadien1und 3.4‐Diazatricyclononen‐Derivaten2–4mit 1.3‐dipolaren Agentien führt zu wachstumsregulierenden tetracyclischen Triazolinen5–8, Isoxazolinen15–17, Pyrazolinen18–22und weiteren Abwandlungspro

ISSN:0022-152X    

DOI:10.1002/jhet.5570180101

出版商:Wiley‐Blackwell    

年代:1981

数据来源: WILEY

摘要:

AbstractPyrazol‐l'‐ylpyridines undergo electrophilic substitution reactions (bromination, chlorination, and nitration) preferentially in the pyrazole ring. There is some evidence of the mutual influence of the pyrazole and the pyridine ring on the reactivity of the system. Some modifications of the substituents were also carried out. A dihydro derivative of a new ring system, pyrazolo[1′,2′‐a]pyrido[2,1‐c][l,2,4]triazine was al

ISSN:0022-152X    

DOI:10.1002/jhet.5570180102

出版商:Wiley‐Blackwell    

年代:1981

数据来源: WILEY

摘要:

Abstract5,6,7,8‐Tetrahydroquinoxaline derivatives containing an oxygen functionality in the 6‐position were prepared by ring closure of suitable 2,3‐disubstituted pyrazines such as6and12. The chemistry of these novel 5,6,7,8‐tetrahydroquinoxalines is di

ISSN:0022-152X    

DOI:10.1002/jhet.5570180103

出版商:Wiley‐Blackwell    

年代:1981

数据来源: WILEY

摘要:

AbstractThe crystal structure of a trisisoxazole derivative is described. The crystals are monoclinic, space group P21/c (Z = 4) with cell dimensions: a = 8.846(4), b = 26.688(7), c = 9.081(4) Ä, β = 142.82(7)0. The structure was refined by full matrix least squares to a final R of 0.060. The molecule is non‐planar and the bond lengths and angles are in the expected range for isoxazole derivati

ISSN:0022-152X    

DOI:10.1002/jhet.5570180104

出版商:Wiley‐Blackwell    

年代:1981

数据来源: WILEY

摘要:

AbstractThe synthesis of some [1]benzopyrano[3,4‐b]pyrazine, ‐[3,4‐d]imidazole, ‐[4,3‐c]imidazole, ‐[4,3‐c]pyrazole and ‐[3,4‐d]isoxazole analogues of cannabi

ISSN:0022-152X    

DOI:10.1002/jhet.5570180105

出版商:Wiley‐Blackwell    

年代:1981

数据来源: WILEY

摘要:

AbstractPreparation of alkyl and glycosyl derivatives of 3,5‐diamino‐4H‐1,2,6‐thiadiazine 1,1‐dioxide (1) is described. Reaction of 1 with dimethyl sulfate gave the 4‐methyl and 2,4‐dimethyl derivatives. With benzyl chloride and allyl bromide C‐4 substituted compounds were obtained. Reaction of the disilyl derivative of 1 with either 2,3,4,6‐tetra‐O‐acetyl‐α‐D‐glucopyranosyl bromide or 1,2,3,4,6‐penta‐O‐acetyl‐β‐D‐glucopyranose in the presence of Friedel‐Crafts catalysts afforded the α and β anomers of the N‐2 nucleoside and the β‐O‐glucoside. When the reaction was performed with 1‐O‐acetyl‐2,3,5‐tri‐O‐benzoyl‐β‐D‐ribofuranose, a β‐C‐glycoside and the α and β anomers of the N‐2 nucleoside were obtained. The structure of the corresponding nucleosides were elucid

ISSN:0022-152X    

DOI:10.1002/jhet.5570180106

出版商:Wiley‐Blackwell    

年代:1981

数据来源: WILEY

摘要:

AbstractThe synthesis of 5‐aminomethyl‐5‐hydroxy‐5H‐dibenzo[a,d]cycloheptene derivatives3was accomplished by two separate routes. The first route involves the reaction of4with Corey's Reagent followed by reaction with either amines or hydrazines. The reaction products with hydrazines (e.g.6) were hydrogenolyzed, either with hydrogen in the presence of platinum, or with hydrazine in the presence of Raney nickel to yield3. The second route to these compounds (3) proceeds by a Reformatsky reaction on4followed by acid‐hydrazide formation and Curtius degradation of8to afford spirooxazolidones9. Compounds9can be alkylated on nitrogen (10), and either9or10hydrolyzed to give the target

ISSN:0022-152X    

DOI:10.1002/jhet.5570180107

出版商:Wiley‐Blackwell    

年代:1981

数据来源: WILEY

摘要:

AbstractEvidence obtained from a single series of compounds demonstrates the need for care when assigning structures to amino‐1,2,4‐oxadiazoles using the methodology described in the literature. Certain synthetic methods can give rise to different position isomers in different ser

ISSN:0022-152X    

DOI:10.1002/jhet.5570180108

出版商:Wiley‐Blackwell    

年代:1981

数据来源: WILEY

摘要:

Abstract4‐Hydrazinothieno[2,3‐d]pyrimidines were cyclized with triethyl orthoformate and formic acid to give 1,2,4‐triazolo[4,3‐c]thieno[3,2‐e]pyrimidines and 1,2,4‐triazolo[2,3‐c]thieno[3,2‐e]pyrimidines depending on the reaction cond

ISSN:0022-152X    

DOI:10.1002/jhet.5570180109

出版商:Wiley‐Blackwell    

年代:1981

数据来源: WILEY

摘要:

AbstractAuthentic samples of 1,3,3‐trimethyl‐2‐(3,4,5‐trimethoxyphenyl)‐4‐methylenepiperidine (Ia) and 2‐(p‐chlorophenyl)‐1,3,3‐trimethyl‐4‐methylenepiperidine (Ib) are prepared by Mannich condensation between 4‐methyl‐1‐methylamino‐3‐pentanone hydrochloride (VI) and an aromatic aldehyde, followed by a Wittig reaction on the resulting 4‐piperidone. Comparing the physical and spectroscopic properties of Ia and Ib with those of the methylene derivatives IIa and IIb obtained as by‐products in the Stevens rearrangement of 1‐benzyl‐1,3,4‐trimethyl‐1,2,5,6‐tetrahydropyridinium salts IIIa and IIIb, respectively, it is shown that the assignment previously made for IIa and IIb is incorrect. Spectroscopic analysis (ir,1H nmr,13C nmr, ms) of these compounds and of its hydrogenation products VIII allows the structural and stereochemical assignment of 11a ascis‐3‐isopropenyl‐1,3‐dimethyl‐2‐(3,4,5‐trimethoxyphenyl)pyrrolidine and of IIb ascis‐2‐(p‐chlorophenyl)‐3‐isopropenyl‐1,3‐dimethylpyrrolidine. The formation of these rearrangem

ISSN:0022-152X    

DOI:10.1002/jhet.5570180110

出版商:Wiley‐Blackwell    

年代:1981

数据来源: WILEY