CHASMANINE AND ITS STRUCTURE

1965 ◽  
Vol 43 (4) ◽  
pp. 825-839 ◽  
Author(s):  
O. Achmatowicz Jr. ◽  
Y. Tsuda ◽  
Léo Marion ◽  
T. Okamoto ◽  
Mitsutaka Natsume ◽  
...  
Keyword(s):  
Cyclic Ether ◽  
Membered Ring ◽  
Hydroxyl Groups ◽  
Lithium Aluminium Hydride ◽  
Allylic Rearrangement ◽  
Rearrangement Product ◽  
Lithium Aluminium ◽  
Pyrolytic Reaction ◽  
Acid Catalyzed ◽  
Tertiary Hydroxyl

The alkaloid chasmanine, C25H41O6N, isolated from A. chasmanthum contains four methoxyl and two hydroxyl groups as well as an imino-ethyl. It undergoes the usual pyrolytic reaction and the unsaturated product, pyrochasmanine, C25H39O5N, gives rise to an acid-catalyzed allylic rearrangement product, isopyrochasmanine. Pyrochasmanine, on treatment with lithium aluminium hydride, is demethoxylated. It can be concluded that the base, like bikhaconine, contains the sequence [Formula: see text]. Chasmanine can be oxidized to a compound containing a cyclopentanone ring so that its second hydroxyl must be secondary and located on a five-membered ring. It is possible to benzoylate the secondary hydroxyl and acetylate the tertiary hydroxyl. The n.m.r. characteristics of the resulting double ester determine the location of these two groups and their stereochemistry. The relative position of two of the remaining methoxyl groups is established via a demethylation reaction resulting in the formation of a cyclic ether. All the chemical reactions studied are in agreement with structure IV (R = R′ = H) for chasmanine. There is, however, no positive proof for the location of the fourth methoxyl and it has been placed in ring A by analogy. An attempted correlation with bikhaconine is described.

Bisquaternary ammonium salts derived from 3α,12α-Diamino-5β-cholane and 3α,12α-Diamino-24-nor-5β-cholane

1971 ◽  
Vol 24 (3) ◽  
pp. 521 ◽  
Author(s):  
S Ahmed ◽  
M Alauddin ◽  
B Caddy ◽  
M Martin-Smith ◽  
WTL Sidwell ◽  
...  
Keyword(s):  
Deoxycholic Acid ◽  
Ammonium Salts ◽  
Hydroxyl Group ◽  
Amino Compound ◽  
Hydroxyl Groups ◽  
Lithium Aluminium Hydride ◽  
Lithium Aluminium ◽  
Polyhydric Alcohols ◽  
Methane Sulphonate ◽  
Methylene Group

The preparation of 3α,12α-bisdimethylamino-5β-cholane dimethiodide, 3α,12α-bisdimethylamino-5β-cholane dimethiodide, 3α,12α- bisdimethylamino-24-nor-5β-cholanedimethiodide, and 3α,12α- bisdimethylamino-24-nor-5β-cholanediethiodide, from deoxycholic acid are described. During this work it was found that attempted copper- quinoline decarboxylation of dehydrocholic acid gives rise to lactol formation, and that what had previously been considered to be 3α,12α- dihydroxy-5β-cholane is a mixture of this compound and 12α,24- dihydroxy-5β-cholane. Comparable selectivity of attack by methanesulphonyl chloride and toluene-p-sulphonyl chloride occurs with various polyhydric alcohols derived from bile acids, as evidenced from the products of reduction of the sulphonates with lithium aluminium hydride. With both 5α- and 5β-cholane derivatives, a C 3 equatorial hydroxyl group exhibits comparable reactivity to the terminal primary hydroxyl group, generated from the bile acid carboxylic group, towards both sulphonyl chlorides. With axial hydroxyl groups at C 7 and C 12, toluene-p-sulphonate formation is much more difficult than methane- sulphonate formation. Reduction by means of lithium aluminium hydride of equatorial sulphonate esters at C 7 and C 12 gives rise to a methylene group, but the axial sulphonates under the same conditions give the axial alcohol. The same clear distinction between equatorial and axial sulphonate esters is not observed at C 3 and C 6, but 17α- methanesulphonyloxy-5α-androstane gives 5α-androstane and the 17β- ester gives 17β-hydroxy-5α-androstane. Reduction of 12-oximino groups in both 5α- and 5β-cholanes with sodium and ethanol, hydrogen in the presence of a catalyst, or lithium aluminium hydride gives solely the 12α-amino compound.

scholarly journals Synthesis of olivomycose (2,6-dideoxy-3-C-methyl-L-arabino-hexose)

1969 ◽  
Vol 47 (23) ◽  
pp. 4467-4471 ◽  
Author(s):  
E. H. Williams ◽  
W. A. Szarek ◽  
J. K. N. Jones
Keyword(s):  
Wittig Reaction ◽  
High Yield ◽  
Lithium Aluminium Hydride ◽  
Ruthenium Tetroxide ◽  
Lithium Aluminium ◽  
Acid Catalyzed ◽  
Hydrolysis Of

Oxidation of methyl 4,6–O-benzylidene-2-deoxy-α-L-arabino-hexopyranoside (1) with ruthenium tetroxide gave the 3-ketone 2 in high yield. A Wittig reaction between methylenetriphenylphosphorane and compound 2 gave methyl 4,6-O-benzylidene-2,3-dideoxy-3-C-methylene-α-L-erythro-hexopyranoside (3), which was hydrated by the oxymercuration–demercuration procedure to afford methyl 4,6-O-benzylidene-2-deoxy-3-C-methyl-α-L-arabino-hexopyranoside (4). The reaction of compound 4 with N-bromosuccinimide gave methyl 4-O-benzoyl-6-bromo-2,6-dideoxy-3-C-methyl-α-L-arabino-hexopyranoside (5) in high yield. Treatment of compound 5 with lithium aluminium hydride followed by acid-catalyzed hydrolysis of the resultant product, gave L-olivomycose (6).

Pinching group stabilization. The synthesis and thermal isomerization of 10-Oxapentacyclo[6.3.2.13,6.01,8.02,7]tetradeca-4,12-diene

1984 ◽  
Vol 37 (6) ◽  
pp. 1293 ◽  
Author(s):  
DN Butler ◽  
RA Russell ◽  
RB Waring ◽  
RN Warrener
Keyword(s):  
Cyclic Ether ◽  
Major Product ◽  
The Novel ◽  
Lithium Aluminium Hydride ◽  
Group Effect ◽  
Flash Vacuum Pyrolysis ◽  
Lithium Aluminium ◽  
Vacuum Pyrolysis ◽  
Site Selective ◽  
Dimethyl Benzene

Sensitized irradiation (benzophenone, 0�, N2, pyrex filter, medium pressure Hg lamp) of dimethyl tricyclo[4.2.1.02,5]nona-3,7-diene-3,4-dicarboxylate (11) in (E)-1,2-dichloroethene yielded a mixture of 1 : 1 adducts (13) and (14) by site selective [2 π+2 π] cycloaddition at the cyclobutene π-bond. Reduction of the (Z)-dichloro isomer(13) with lithium aluminium hydride formed the related diol (16) which is the immediate precursor to the cyclic ether (18). Dechlorination of (18) with zinc in ethanol forms the title diene (19). Thermolysis of the polycyclic diester (20) affords the fragmentation products cyclopentadiene and dimethyl benzene-1,4-dicarboxylate. In contrast, the title compound (19) containing the cyclic ether ring was more stable and yielded the novel isomer (28) as the major product only upon flash vacuum pyrolysis at 560�(1.5 × 10-2 Torr). This difference in behaviour is attributed to a pinching group effect exerted by the cyclic ether present in (19).

SOME STRUCTURAL FEATURES OF DELCOSINE

1958 ◽  
Vol 36 (5) ◽  
pp. 766-770 ◽  
Author(s):  
Ragini Anet ◽  
Léo Marion
Keyword(s):  
Heterocyclic Ring ◽  
Structural Features ◽  
Membered Ring ◽  
Hydroxyl Groups ◽  
Supporting Evidence ◽  
Methylene Group ◽  
Tertiary Hydroxyl

The alkaloid delcosine has previously been assigned tentatively the same carbon–nitrogen skeleton as lycoctonine to which it appears to be closely related in properties. Oxidation experiments now reported provide supporting evidence of the presence of two vicinal tertiary hydroxyl groups attached to a five- and a six-membered ring that are directly linked together at the two carbons carrying the hydroxyls. There is a methoxyl in a position β to the tertiary hydroxyl of the six-membered ring. Evidence is also provided as to the size of the heterocyclic ring and the presence of a methylene group next to the nitrogen.

The application of lithium aluminium hydride to the preparation of some amino-alkanols

1951 ◽  
Vol 1 (10) ◽  
pp. 469-472
Author(s):  
A. W. D. Avison
Keyword(s):  
Lithium Aluminium Hydride ◽  
Lithium Aluminium

Convenient Synthesis of (Z)-7- and (E)-9-dodecene-1-yl Acetate, Components of Some Lepidoptera Insect Sex Pheromone

2017 ◽  
Vol 68 (1) ◽  
pp. 180-185
Author(s):  
Adriana Maria Andreica ◽  
Lucia Gansca ◽  
Irina Ciotlaus ◽  
Ioan Oprean
Keyword(s):  
Sex Pheromone ◽  
Coupling Reaction ◽  
Coupling Scheme ◽  
Lithium Aluminium Hydride ◽  
Terminal Alkyne ◽  
Mercury Derivative ◽  
Lithium Aluminium ◽  
Convenient Synthesis ◽  
Practical Synthesis ◽  
Insect Sex

Were developed new and practical synthesis of (Z)-7-dodecene-1-yl acetate and (E)-9-dodecene-1-yl acetate. The routes involve, as the key step, the use of the mercury derivative of the terminal-alkyne w-functionalised as intermediate. The synthesis of (Z)-7-dodecene-1-yl acetate was based on a C6+C2=C8 and C8+C4=C12 coupling scheme, starting from 1,6-hexane-diol. The first coupling reaction took place between 1-tert-butoxy-6-bromo-hexane and lithium acetylide-ethylendiamine complex obtaining 1-tert-butoxy-oct-7-yne, which is transformed in di[tert-butoxy-oct-7-yne]mercury. The mercury derivative was directly lithiated and then alkylated with 1-bromobutane obtaining 1-tert-butoxy-dodec-7-yne. After acetylation and reduction with lithium aluminium hydride of 7-dodecyne-1-yl acetate gave (Z)-7-dodecene-1-yl acetate with 96 % purity. The synthesis of (E)-9-dodecene-1-yl acetate was based on a C8+C2=C10 and C10+C2=C12 coupling scheme, starting from 1,8-octane-diol. The first coupling reaction took place between 1-tert-butoxy-8-bromo-octane and lithium acetylide-ethylendiamine complex obtaining 1-tert-butoxy-dec-9-yne, which is transformed in di[tert-butoxy-dec-9-yne]mercury. The mercury derivative was directly lithiated and then alkylated with 1-bromoethane obtaining 1-tert-butoxy-dodec-9-yne. After reduction with lithium aluminium hydride of 1-tert-butoxy-(E)-9-dodecene and acetylation was obtained (E)-9-dodecene-1-yl acetate with 97 % purity.

3-(s-Hydrindacen-4-yl)propylamines and 4-(s-hydrindacen-4-yl)butylamines; Synthesis and pharmacological screening

1981 ◽  
Vol 46 (8) ◽  
pp. 1800-1807 ◽  
Author(s):  
Zdeněk Vejdělek ◽  
Marie Bartošová ◽  
Miroslav Protiva
Keyword(s):  
Malonic Acid ◽  
Local Anaesthetics ◽  
Lithium Aluminium Hydride ◽  
Spasmolytic Activity ◽  
Lithium Aluminium ◽  
Malonic Acid Derivatives ◽  
Pharmacological Screening ◽  
Hydroxyethyl Piperazine

4-Chloromethyl-s-hydrindacene (VIIa) was transformed via the malonic acid derivatives VIIIa and IXa to the acid Xb which afforded in four steps the homological acid Xc. Reactions of chlorides of both acids (XIbc ) with dimethylamine, 1-methylpiperazine and 1-(2-hydroxyethyl)piperazine led to the amides XIIbc-XIVbc which were reduced with lithium aluminium hydride to the title compounds IVcd-VIcd. The amines obtained show central neuroleptic effects only in subtoxic doses; they are also potent local anaesthetics and have significant spasmolytic activity of the neurotropic as well as musculotropic type.

Reaction of 1,4-dibromohexafluoro-2-butene with O- and N-nucleophiles

1988 ◽  
Vol 53 (3) ◽  
pp. 619-625 ◽  
Author(s):  
Ivan Hemer ◽  
Věra Moravcová ◽  
Václav Dědek
Keyword(s):  
Kinetic Study ◽  
Sodium Methoxide ◽  
Allylic Rearrangement ◽  
Rearrangement Product

Reaction of 1,4-dibromohexafluoro-2-butene (I) with sodium methoxide, ethoxide or isopropoxide in the corresponding alcohols proceeds with allylic rearrangement under formation of 3-alkoxy-4-bromohexafluoro-1-butenes II-IV. A kinetic study has proven the SN2’ mechanism for reaction of I with potassium phenoxide leading to 4-bromo-3-phenoxyhexafluoro-1-butene (V). Also the reaction of I with ammonia, affording 3-amino-4-bromo-2,4,4-trifluoro-2-butenenitrile (IX), is compatible with the allylic rearrangement by SN2’ mechanism. On the contrary, reaction of I with diethylamine gave no rearrangement product and, after hydrolysis, afforded N,N-diethyl-4-bromo-2,3,3,4,4-pentafluorobutanamide (XVI) and N,N-diethyl-4-bromo-2,3,4,4-tetrafluoro-2-butenamide (XVII) in the ratio 85:15.

Substituted N,N-Dimethyl-3-(phenylthio)- and -4-(phenylthio)benzylamines

1992 ◽  
Vol 57 (1) ◽  
pp. 194-203 ◽  
Author(s):  
Karel Šindelář ◽  
Vojtěch Kmoníček ◽  
Marta Hrubantová ◽  
Zdeněk Polívka
Keyword(s):  
Serotonin Receptors ◽  
Hydrobromic Acid ◽  
Antidepressant Activity ◽  
Benzoic Acids ◽  
Lithium Aluminium Hydride ◽  
Acid Chlorides ◽  
Activity Inhibition ◽  
Lithium Aluminium ◽  
The Brain

(Arylthio)benzoic acids IIa - IIe and VIb - VId were transformed via the acid chlorides to the N,N-dimethylamides which were reduced either with diborane "in situ" or with lithium aluminium hydride to N,N-dimethyl-(arylthio)benzylamines Ia - Ie and Vb - Vd. Leuckart reaction of the aldehydes IX and X with dimethylformamide and formic acid afforded directly the amines Va and Ve. Demethylation of the methoxy compounds Ia and Ve with hydrobromic acid resulted in the phenolic amines If and Vf. The most interesting N,N-dimethyl-4-(phenylthio)benzylamine (Va) hydrochloride showed affinity to cholinergic and 5-HT2 serotonin receptors in the rat brain and some properties considered indicative of antidepressant activity (inhibition of serotonin re-uptake in the brain and potentiation of yohimbine toxicity in mice).

Sign in / Sign up

Export Citation Format

Share Document