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.

THE STRUCTURE OF MITRAPHYLLINE

1958 ◽  
Vol 36 (7) ◽  
pp. 1031-1038 ◽  
Author(s):  
J. C. Seaton ◽  
R. Tondeur ◽  
Léo Marion
Keyword(s):  
Double Bond ◽  
Experimental Evidence ◽  
Aromatic Amine ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Mineral Acid ◽  
Lithium Aluminum ◽  
Spectroscopic Evidence ◽  
Mild Conditions ◽  
Total Structure

Mitraphylline (C21H24O4N2) contains a carbomethoxyl group, and on hydrolysis gives rise to mitraphyllic acid. Spectroscopic evidence shows that the alkaloid contains two chromophores, one characteristic of an oxindole and one corresponding to the grouping CH3OOC—Ć==CH.OR. On treatment with dilute mineral acid the alkaloid gives rise to mitraphyllal (C19H24O3N2), which is a hemiacetal that no longer contains the isolated double bond and the carbomethoxyl group originally present in the alkaloid. Reduction of mitraphyllal by the Wolff–Kishner reaction gives mitraphyllane (C19H26O2N2). The dehydrogenation of mitraphyllal produced 3,4-diethylpyridine and 3-ethyloxindole. The action of lithium aluminum hydride on mitraphylline under mild conditions gave rise to mitraphyllol by reduction of the carbomethoxyl group, and under more vigorous conditions to dihydrodesoxy-mitraphyllol by reduction of the oxindole carbonyl as well. This last product has the properties of an aromatic amine. On the basis of the new experimental evidence, a total structure of mitraphylline is derived.

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 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.

ChemInform Abstract: THE ACTION OF LITHIUM-ALUMINUM HYDRIDE ON A DIENOL IN STEROID SERIES. A NEW CASE OF DOUBLE BOND REDUCTION

1978 ◽  
Vol 9 (15) ◽  
Author(s):  
M. FETIZON ◽  
HOA TRAN HUY HOA TRAN HUY ◽  
P. MOURGUES
Keyword(s):  
Double Bond ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Lithium Aluminum

Reductions of Thio Acids with Lithium Aluminum Hydride and Sodium Borohydride

1971 ◽  
Vol 36 (21) ◽  
pp. 3235-3236 ◽  
Author(s):  
Gene Heasley
Keyword(s):  
Sodium Borohydride ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Lithium Aluminum

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.

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