THE STRUCTURE AND STEREOISOMERISM OF THREE MITRAGYNA ALKALOIDS

1960 ◽  
Vol 38 (7) ◽  
pp. 1035-1042 ◽  
Author(s):  
J. C. Seaton ◽  
M. D. Nair ◽  
O. E. Edwards ◽  
Léo Marion
Keyword(s):  
Hydrochloric Acid ◽  
Dilute Hydrochloric Acid ◽  
Lithium Aluminum Hydride ◽  
Mercuric Acetate ◽  
Aluminum Hydride ◽  
Spectroscopic Properties ◽  
Membered Ring ◽  
Reduction Product ◽  
Lithium Aluminum ◽  
Lactam Carbonyl

Isorhyncophylline, the isomer into which rhyncophylline is convertible, has been found to occur in nature. Both bases are interconvertible. Isorhyncophylline on hydrolysis with dilute hydrochloric acid is converted to an aldehyde reducible to isorhyncophyllol. When the aldehyde is reduced in the Wolff–Kishner reaction, it is also isomerized and the product is isorhyncophyllane. This reduction product is oxidized by mercuric acetate to a neutral dilactam which still contains the oxindole carbonyl and further contains a new lactam carbonyl present in a six-membered ring. Reduction of the dilactam with lithium aluminum hydride gave a product having the spectroscopic properties of an indole. This confirms the assumption previously made that in rhyncophylline, ring C is five-membered. The isomerization of rhyncophylline, mitraphylline, and formosanine is described. Formosanine has been shown to be identical with uncarine-B and thus uncarine-A is the iso base derivable from formosanine.

Total Synthesis of Several Monodeoxy and Dideoxy-DL-hexopyranoses from 6,8-Dioxabicyclo[3.2.1]oct-2-ene and 6,8-Dioxabicyclo[3.2.1]oct-3-ene

1971 ◽  
Vol 49 (12) ◽  
pp. 2132-2138 ◽  
Author(s):  
T. P. Murray ◽  
U. P. Singh ◽  
R. K. Brown
Keyword(s):  
Hydrochloric Acid ◽  
Total Synthesis ◽  
Dilute Hydrochloric Acid ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Lithium Aluminum ◽  
Osmic Acid ◽  
Aqueous Base

Reaction of osmic acid with 6,8-dioxabicyclo[3.2.1]oct-3-ene (1) gave 1,6-anhydro-4-deoxy-β-DL-ribo-hexopyranose (3, R = H) which was hydrolyzed to 4-deoxy-α,β-DL-ribo-hexopyranose (4, R = H). Conversion of 1 to 1,6:2,3-dianhydro-4-deoxy-β-DL-ribo-hexopyranose (5) followed by treatment of 5 with lithium aluminum hydride, gave 1,6-anhydro-3,4-dideoxy-β-DL-erythro-hexopyranose (6, R = H), and this in turn was hydrolyzed to 3,4-dideoxy-α,β-DL-erythro-hexopyranose (7, R = H).Reaction of osmic acid with 6,8-dioxabicyclo[3.2.1]oct-2-ene (2) gave 1,6-anhydro-2-deoxy-β-DL-riob-hexopyranose (8, R = H), which was hydrolyzed to 2-deoxy-DL-riob-hexopyranose (9, R = H). Compound 2 was converted to 1,6:3,4-dianhydro-2-deoxy-β-DL-ribo-hexopyranose (10) which was hydrolyzed by aqueous base to 1,6-anhydro-2-deoxy-β-DL-arabino-hexopyranose (12) and this in turn was hydrolyzed by dilute hydrochloric acid to 2-deoxy-α,β-DL-arabino-hexopyranose (2-deoxy-DL-glucose) (13). The reaction of 10 with lithium aluminum hydride gave 1,6-anhydro-2,3-dideoxy-β-DL-erythro-hexopy-ranose (14).Yields were good to excellent in each of the above reactions.

THE STRUCTURE OF RHYNCOPHYLLINE

1957 ◽  
Vol 35 (10) ◽  
pp. 1102-1108 ◽  
Author(s):  
J. C. Seaton ◽  
Léo Marion
Keyword(s):  
Double Bond ◽  
Hydrochloric Acid ◽  
Sodium Borohydride ◽  
Dilute Hydrochloric Acid ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Aldehyde Group ◽  
Lithium Aluminum ◽  
Total Structure ◽  
Hydrolysis Of

It is shown that hydrolysis of rhyncophylline with dilute hydrochloric acid gives rhyncophyllal (C19H24O2N2), which contains an aldehyde group but no longer contains the methoxyl, the isolated double bond, and the carbomethoxy group originally present in the alkaloid. Rhyncophyllal is reduced by sodium borohydride to the corresponding alcohol, rhyncophyllal, and this is further reduced by lithium aluminum hydride to dihydrodesoxy-rhyncophyllal (C19H28ON2), which shows the properties of an aromatic amine. Reduction of rhyncophyllal by the Wolff-Kishner reaction gives rhyncophyllane (C19H26ON2), which, when dehydrogenated over palladium–charcoal, yields 3,4-diethylpyridine. Direct dehydrogenation of rhyncophyllal produces β-collidine. On the basis of these as well as previously described results a total structure for rhyncophylline is derived.

PSEUDACONITINE, AND THE STEREOCHEMICAL RELATIONSHIP OF THE HIGHLY OXYGENATED ACONITE ALKALOIDS

1963 ◽  
Vol 41 (6) ◽  
pp. 1485-1489 ◽  
Author(s):  
Y. Tsuda ◽  
Léo Marion
Keyword(s):  
Acetic Acid ◽  
Absolute Configuration ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Reduction Product ◽  
Lithium Aluminum ◽  
Partial Hydrolysis ◽  
Previous Knowledge ◽  
Relationship Of ◽  
Hydrolysis Of

An alkaloid isolated from Aconitum spicatum Stapf has been found to be identical not only with the originally described pseudaconitine but also with 'α-pseudaconitine'. The product of the partial hydrolysis of the base, i.e., veratroylpseudaconine, is dextrorotatory, and not laevorotatory as recorded in the old literature. On heating, pseudaconitine undergoes pyrolysis, loses the elements of acetic acid, and gives rise to pyropseudaconitine. This substance, on treatment with lithium aluminum hydride, is converted to demethoxyisopyropseudaconine which is identical with the Wolff–Kishner reduction product of pyraconine. This correlation establishes that pseudaconitine and aconitine possess the same absolute configuration, which, in the light of previous knowledge, is extended also to indaconitine, delphinine, mesaconitine, and jesaconitine.

THE REACTION OF DIETHYL AZODICARBOXYLATE WITH DIHYDROGELSEMINE

1955 ◽  
Vol 33 (4) ◽  
pp. 604-609 ◽  
Author(s):  
Thelma Habgood ◽  
Léo Marion
Keyword(s):  
Infrared Spectrum ◽  
Methyl Ether ◽  
Sodium Borohydride ◽  
Lithium Aluminum Hydride ◽  
Chromic Acid ◽  
Aluminum Hydride ◽  
Membered Ring ◽  
Lithium Aluminum ◽  
Diethyl Azodicarboxylate ◽  
Methylene Group

Dihydrogelsemine reacts with diethyl azodicarboxylate yielding a carbinolamine which forms a methyl ether. Both this ether and the carbinolamine base can be oxidized by chromic acid to the same neutral lactam. That there has been no rearrangement of the carbon skeleton during these reactions is shown by reduction of the methyl ether of the carbinolamine with sodium borohydride to dihydrogelsemine and by reduction of the lactam with lithium aluminum hydride to tetrahydrodesoxygelsemine. It is concluded that both dihydrogelsemine and gelsemine contain a methylene group adjacent to N(b), and from the infrared spectrum of the lactam of dihydrogelsemine, N(b) appears to be part of a five-membered ring.

Berberidic acid

1979 ◽  
Vol 57 (13) ◽  
pp. 1647-1651 ◽  
Author(s):  
P. Chinnasamy ◽  
M. Shamma
Keyword(s):  
Lithium Aluminum Hydride ◽  
Mercuric Acetate ◽  
Dimethyl Ester ◽  
Pyridinium Salt ◽  
Aluminum Hydride ◽  
Lithium Aluminum ◽  
Acid Oxidation ◽  
Hydride Reduction ◽  
Sodium Borohydride Reduction ◽  
Nitric Acid Oxidation

Berberidic acid (2), obtained by nitric acid oxidation of berberine (1), can be esterified to diester 3, or to monoesters 4 and 5. Sodium borohydride reduction of 4 provides γ-lactone 6 which can be oxidized with iodine to pyridinium salt 7. In like fashion, monoester 5 leads to γ-lactone 8 which is oxidized by mercuric acetate to salt 9. Berberidic acid dimethyl ester (3) is hydrogenated to allo hexahydro diester 10 from which normal diester 11 can be derived by base isomerization. Hydrogenation of lactone 6 produces allo lactone 14 whose further reduction with lithium aluminum hydride gives diol 15. This same diol can also be obtained from the lithium aluminum hydride reduction of hexahydro diester 10. Alternatively, lithium aluminum hydride reduction of diester 11 gives rise to diol 16, diastereomeric with 15. Catalytic hydrogenation of lactone 8 provides normal lactone 18 which is transformed to diol 6 by lithium aluminum hydride.

THE HYDROGENOLYSIS OF 3-HYDROXYMETHYLINDOLE AND OTHER INDOLE DERIVATIVES WITH LITHIUM ALUMINUM HYDRIDE

1953 ◽  
Vol 31 (9) ◽  
pp. 775-784 ◽  
Author(s):  
Edward Leete ◽  
Léo Marion
Keyword(s):  
Carboxylic Acid ◽  
Sodium Hydroxide ◽  
Ethyl Ester ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Reduction Product ◽  
Alkaline Media ◽  
Lithium Aluminum ◽  
Indole Derivatives ◽  
Alkyl Ethers

Indole-3-aldehyde, indole-3-carboxylic acid and its ethyl ester were reduced by excess lithium aluminum hydride to skatole. The expected reduction product, 3-hydroxymethylindole, was obtained by the action of sodium hydroxide on gramine methiodide. It and its alkyl ethers were readily reduced to skatole. 3-Hydroxymethylindole underwent self-condensation to 3,3′-di-indolylmethane in neutral and alkaline media, and with acidic reagents was converted to an oxygen-free polymeric substance. The mechanism of these reactions and of the hydrogenolysis is discussed

Derivative Formation for the Confirmation of Endosulfan by Gas Chromatography

1969 ◽  
Vol 52 (6) ◽  
pp. 1240-1248
Author(s):  
A S Y Chal
Keyword(s):  
Gas Chromatography ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Reduction Product ◽  
Lithium Aluminum ◽  
Agricultural Crops ◽  
Sample Extract

Abstract Chemical conversions followed by GLC analysis are described for the confirmation of residues of α- and β-endosulfan in agricultural crops. Both isomers were reduced to the same diol by lithium aluminum hydride in tetrahydrofuran. Subsequent silylation to the disilyl ether can be used for the routine confirmation of both isomers down to a level of 0.02 p pm in a 10 g sample extract. Alternatively, the insecticide or its reduction product can be acetylated. By this procedure, 0.03 ppm or more of the parent insecticide can be identified in a 10 g sample extract.

REDUCTION OF STEROIDS USING LITHIUM ALUMINUM HYDRIDE

1949 ◽  
Vol 27b (12) ◽  
pp. 902-906 ◽  
Author(s):  
G. Papineau-Couture ◽  
Gordon A. Grant ◽  
E. M. Richardson
Keyword(s):  
Carbonyl Group ◽  
Phthalic Anhydride ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Selective Reduction ◽  
Reduction Product ◽  
Lithium Aluminum ◽  
Partial Reduction ◽  
Simultaneous Production

Lithium aluminum hydride has been used successfully in the partial reduction of phthalic anhydride to phthalide, in the selective reduction of the carbonyl group of dehydroisoandrosterone-3-acetate, and in the reduction of oestrone acetate to α-oestradiol without simultaneous production of the β-isomer. A new reduction product of Δ5-3(β)hydroxyetiobilienic acid, Δ9,14-2,13-dimethyl-7(β)hydroxy-2-hydroxymethyl-1-hydroxyethyl dodecahydrophenanthrene, is also described.

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