Derivatives of oximes. II. Reduction of O- and N-alkyl oximes with lithium aluminium hydride

1955 ◽  
Vol 20 (1) ◽  
pp. 202-209 ◽  
Author(s):  
O. Exner
Keyword(s):  
Lithium Aluminium Hydride ◽  
Lithium Aluminium ◽  
Derivatives Of

4,5-Seco-4,6-cyclosteroids. III. Observations on the course of reductive rearrangement of 6β-Bromo-4β,5-epoxy-5β-cholestan-3β-ol

1969 ◽  
Vol 22 (4) ◽  
pp. 807 ◽  
Author(s):  
DJ Collins ◽  
JJ Hobbs ◽  
RJ Rawson
Keyword(s):  
Hydrogen Bromide ◽  
High Yield ◽  
Lithium Aluminium Hydride ◽  
Experimental Conditions ◽  
Lithium Aluminium ◽  
Reaction Proceeds ◽  
Derivatives Of

It has been shown that reductive rearrangement of 6β-bromo-4β,5-epoxy- 5β-cholestan-3β-ol (I) to 4,5-seco-4,6-cycle-6β-cholestane-3β,5α-diol (IXa) with lithium aluminium hydride in tetrahydrofuran proceeds via 6β-bromo-5β-cholestane-3β,5-diol (IIa). Relevant reactions of the latter and the corresponding 3-ketone are discussed. ��� Similar conversion of the 3-epimer of (I) into 4,5-seco-4,6-cyclo- 6β-cholestane-3α,5α-diol (XIIIa) in high yield indicates that reductive rearrangement of the 6β-bromo-5β-hydroxy moiety proceeds without participation of the 3-aluminate complex. Some derivatives of (XIIIa) are described. ��� Experimental conditions required for the conversion of (I) into (IXa) are defined. ��� Combined evidence indicates that the reaction proceeds in a concerted manner by essentially base-catalysed, 1,3-elimination of hydrogen bromide from diol (IIa) with 4,5-bond migration to give the formal intermediate 3β-hydroxy-4,5-seco-4,6-cyclo-6β-cholestan-5-one (VI), further reduced to (IXa).

Preparation of 12,20-disubstituted lupane derivatives

1979 ◽  
Vol 44 (1) ◽  
pp. 194-210 ◽  
Author(s):  
Vladimír Pouzar ◽  
Alois Vystrčil
Keyword(s):  
Hydroxy Group ◽  
Sodium Borohydride ◽  
Nmr Spectra ◽  
Unsaturated Ketone ◽  
Lithium Aluminium Hydride ◽  
H Nmr ◽  
Unsaturated Alcohols ◽  
Lithium Aluminium ◽  
Primary Hydroxy Group ◽  
Derivatives Of

Ketoester I was reduced to diol VI. The higher reactivity of its primary hydroxy group was made use of for the preparation of 12α-hydroxy derivatives VII, VIII and X the oxidation of which led to oxo derivatives XII, XIII and XIV. The reduction of the 12-oxo group in compounds XII and XIV with lithium aluminium hydride takes place stereospecifically under formation of 12α-hydroxy derivatives VII and X, while on reduction with sodium in 1-propanol corresponding 12β-hydroxy derivatives XV and XVI are also formed. Reduction of the unsaturated ketone XVII with sodium borohydride gave unsaturated alcohols XVIII and XX. As acetoxy ketone XXIV was obtained from olefin XIX in a 12% yield only, its alternative preparation was carried out from acetoxy ketone XXXIV via the intermediates XXXII, XXXV, XXVIII and XXXI in an overall yield of 27%. The structures of the derivatives of 12-lupene (III, V, XVII, XIX and XXI), 12-lupanol (II, VII, X, XV, XXXI and XXVII) and 12-lupanone (I, XII, XIII, XIV, XXIII, XXIV, XXXIII and XXXIV) were confirmed by the analysis of their 1H NMR spectra.

N-(Aminoacyl) and N-(aminoalkyl) derivatives of 4-cyclopentylaniline and N-ethyl-4-cyclopentylaniline; Synthesis and pharmacological screening

1983 ◽  
Vol 48 (1) ◽  
pp. 156-162 ◽  
Author(s):  
Zdeněk Vejdělek ◽  
Marie Bartošová ◽  
Miroslav Protiva
Keyword(s):  
Lithium Aluminium Hydride ◽  
Substitution Reactions ◽  
Rotarod Test ◽  
Lithium Aluminium ◽  
Local Anaesthetic Effect ◽  
Anorectic Effect ◽  
Pharmacological Screening ◽  
Derivatives Of ◽  
Higher Doses ◽  
Anaesthetic Effect

Acylation of 4-cyclopentylaniline (I) with chloracetyl chloride, 3-chloropropionyl chloride, 4-chlorobutyryl chloride and 2-bromo-4-methylvaleryl bromide gave the halogenoacyl derivatives IV - VII out of which the first two were subjected to substitution reactions with diethylamine and piperidine. The N-(aminoacyl) derivatives VIII - XI obtained were reduced with lithium aluminium hydride to the N-(aminoalkyl) derivatives XII and XV. N-Ethyl-4-cyclopentylaniline (XVI), prepared by reduction of N-(4-cyclopentylphenyl)acetamide (II), was similarly transformed via the chloroacetyl derivative XVII to the amide XVIII and the diamine XIX. Salts of the compounds prepared (amino amides and diamines) bring about in higher doses central excitation which is apparently in close connection with the found discoordinating effect of a part of products (VIII - XI, XIII) in the rotarod test, further with the antireserpine effects in the tests of antagonization of reserpine ptosis and hypothermia (VIII, X, XII, XIII) and finally with the anorectic effect of compound X. All substances showed a mild spasmolytic effect of the anticholinergic type. On the other hand, the expected local anaesthetic effect was found only with compounds VIII, XVIII, XIX.

Synthesis of 1,6-Anhydro-2,3,4-trideoxy-2,3-epimino- and 1,6-Anhydro-2,3,4-trideoxy-3,4-epimino-β-D-hexopyranoses and Their NMR and Infrared Spectra

2004 ◽  
Vol 69 (10) ◽  
pp. 1939-1954 ◽  
Author(s):  
Jindřich Karban ◽  
Miloš Buděšínský ◽  
Jiří Kroutil
Keyword(s):  
Infrared Spectra ◽  
Lithium Aluminium Hydride ◽  
Aziridine Ring ◽  
Hydride Reduction ◽  
Lithium Aluminium ◽  
Complete Series ◽  
Derivatives Of ◽  
Unusual Formation

A complete series of 2,3,4-trideoxy-2,3-epimino and 2,3,4-trideoxy-3,4-epimino derivatives of 1,6-anhydro-β-D-hexopyranoses were prepared by lithium aluminium hydride reduction of vicinal trans azido tosylates. Unusual formation of the aziridine ring from precursors with the trans-diequatorial arrangement of the reacting groups was observed. NMR and infrared spectra of the aziridines are discussed.

N-(piperazinoacyl) and N-(piperazinoalkyl) derivatives of 4-cyclopentylaniline and related compounds: Synthesis and pharmacological screening

1986 ◽  
Vol 51 (7) ◽  
pp. 1494-1502
Author(s):  
Zdeněk Vejdělek ◽  
Miroslav Protiva
Keyword(s):  
Similar Reaction ◽  
Lithium Aluminium Hydride ◽  
Antispasmodic Activity ◽  
Analgesic Effects ◽  
Basic Amides ◽  
Lithium Aluminium ◽  
Propionyl Chloride ◽  
Pharmacological Screening ◽  
Derivatives Of ◽  
Related Compounds

Five N-(4-cyclopentylphenyl)haloalkanecarboxamides were reacted with 1-methylpiperazine and 1-(2-hydroxyethyl)piperazine to give the corresponding N-(4-cyclopentylphenyl)piperazinoalkanecarboxamides Iab -Vab. Their reduction with lithium aluminium hydride afforded the triamines VIIab - XIab. Acylation of the N-(4-methylpiperazino)alkyl-4-cyclopentylanilines Xa and XIa with propionyl chloride resulted in the propionanilides XIVa and XVa, whereas a similar reaction of the N-(4-(2-hydroxyethyl)piperazino)alkyl-4-cyclopentylanilines VIIb and IXb - XIb produced the propionoxypropionanilides XIIc - XVc. Ethanolysis of these compounds afforded corresponding hydroxypropionanilides XIIb - XVb. Many of the basic amides showed local anaesthetic and papaverine-like antispasmodic activity. The propionanilides XIIb, XIVc, and XVa proved interesting analgesic effects in the peritoneal test in mice.

Antiandrogenic A-homo-B,19-dinor-analogues of androgens from 6β-chloro-5-methyl-19-nor-5β-androst-9-enes

1989 ◽  
Vol 54 (5) ◽  
pp. 1318-1326 ◽  
Author(s):  
Alexander Kasal
Keyword(s):  
Partial Hydrolysis ◽  
Lithium Aluminium Hydride ◽  
Lithium Aluminium ◽  
Selective Acylation ◽  
Chloro Derivatives ◽  
Hydrolysis Of ◽  
Derivatives Of ◽  
Antiandrogenic Activity

6β-Chloro derivatives of 5-methyl-19-nor-5β-androst-9-enes (Westphalen diol type) with oxygen functionalities in positions 3 and 17 were converted into diene VI by treatment with lithium aluminium hydride. The lipophilic product of hydrogenation of VI was shown to be 4aα-methyl-A-homo-B,19-dinor-5β,10α-androstane-3β,17β-diol (IX). Various paths leading to dihydrotestosteron analogues, e.g. selective acylation or oxidation of diol IX and partial hydrolysis of diacetate X, have been realized. 17β-Hydroxy-4aα-methyl-A-homo-B,19-dinor-5β,10α-androstan-3-one (XVI) has been found to exhibit antiandrogenic activity.

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