DERIVATIVES OF DEHYDROABIETIC AND PODOCARPIC ACIDS

1963 ◽  
Vol 41 (8) ◽  
pp. 1924-1936 ◽  
Author(s):  
Ernest Wenkert ◽  
Peter Beak ◽  
Richard W. J. Carney ◽  
James W. Chamberlin ◽  
David B. R. Johnston ◽  
...  
Keyword(s):  
Methyl Esters ◽  
Resin Acid ◽  
Aluminum Hydride ◽  
Resin Acids ◽  
Lithium Aluminum ◽  
Hydride Reduction ◽  
Rate Of Hydrolysis ◽  
Keto Derivative ◽  
Hydrolysis Of ◽  
Derivatives Of

The lithium aluminum hydride reduction of nitriles in the aromatic resin acid series to aldimines and the conversion of the products to other derivatives are described. The effect of the stereochemistry of the nitriles on the rate of reduction is noted. The transformation of dehydroabietane into a dehydro product is indicated. The syntheses of a desoxydecarboxy-5,6-dehydro-7-keto derivative of podocarpic acid and its optical antipode are discussed. The stereochemistry of hydrogenation of 5,6-dehydro derivatives of podocarpic acid is reported. The effect of a 7-keto group on the rate of hydrolysis of methyl esters of aromatic resin acids is illustrated. The reactions of 6-bromo-7-keto derivatives of methyl podocarpate with bases are portrayed.

BIOCHEMISTRY OF THE USTILAGINALES: VIII. THE STRUCTURES AND CONFIGURATIONS OF THE USTILIC ACIDS

1953 ◽  
Vol 31 (4) ◽  
pp. 396-417 ◽  
Author(s):  
R. U. Lemieux
Keyword(s):  
Methyl Esters ◽  
Active Form ◽  
Aluminum Hydride ◽  
Optically Active ◽  
Lithium Aluminum ◽  
Acid Oxidation ◽  
Chromic Acid Oxidation ◽  
Pure Compounds ◽  
Hydrolysis Of ◽  
Derivatives Of

Methanolysis of ustilagic acid and hydrolysis of the methyl esters formed yielded a crystalline acidic fraction which was essentially a mixture of two substances termed the ustilic acids A and B. The acids were separated as their iso-propylidene derivatives. The ustilic acids cocrystallize to mixtures with melting points intermediate between those of the pure compounds. Conversion of ustilic acid A, m.p. 112–113 °C, [α]D −8° in methanol, which made up about 70% of the mixture, by hydrogenolysis to palmitic acid, by oxidation with chromic oxide to pentadecanedioic acid, and by lead tetraacetate oxidation followed by hydrogenation to 15-hydroxypentadecanoic acid showed the substance to be an optically active form of 15,16-dihydroxyhexadecanoic acid. Conversion of ustilic acid B, m.p. 140–141 °C, [α]D−10° in methanol, by sodium bismuthate oxidation followed by hydrogenation to 1,14-dihydroxytetradecane, by chromic acid oxidation of its methyl ester followed by hydrolysis of the product, and peroxide oxidation of the α-keto acid thus formed to tetradecanedioic acid, and by hydrogenolysis of the C2-carbon atom through a series of reactions to ustilic acid A, showed the substance to be an optically active form of 2,15,16-trihydroxy-hexadecanoic acid. Optically active forms of 2,15-dihydroxypentadecanoic and 2-hydroxypentadecanoic acids were prepared from ustilic acid B. Application of certain empirical rules of rotation to derivatives of these 2-hydroxyacids showed them to possess the D-configuration. Reduction of ustilic acid B with lithium aluminum hydride gave meso-1,2,15,16-tetrahydroxyhexadecane. Thus, ustilic acid B was the 2D,15D,16-trihydroxyhexadecanoic acid and the ustilic acid A was the 15D,16-dihydroxyhexadecanoic acid. Several derivatives of the above described acids were prepared.

scholarly journals Novel Amino Acid Derivatives of Quinolines as Potential Antibacterial and Fluorophore Agents

2020 ◽  
Vol 88 (4) ◽  
pp. 57
Author(s):  
Oussama Moussaoui ◽  
Rajendra Bhadane ◽  
Riham Sghyar ◽  
El Mestafa El Hadrami ◽  
Soukaina El Amrani ◽  
...  
Keyword(s):  
Amino Acid ◽  
Methyl Esters ◽  
Amino Acid Derivatives ◽  
Bacterial Strains ◽  
Fluorescent Properties ◽  
Topoisomerase Iv ◽  
Microdilution Method ◽  
Hydrolysis Of ◽  
Derivatives Of

A new series of amino acid derivatives of quinolines was synthesized through the hydrolysis of amino acid methyl esters of quinoline carboxamides with alkali hydroxide. The compounds were purified on silica gel by column chromatography and further characterized by TLC, NMR and ESI-TOF mass spectrometry. All compounds were screened for in vitro antimicrobial activity against different bacterial strains using the microdilution method. Most of the synthesized amino acid-quinolines show more potent or equipotent inhibitory action against the tested bacteria than their correspond esters. In addition, many of them exhibit fluorescent properties and could possibly be utilized as fluorophores. Molecular docking and simulation studies of the compounds at putative bacterial target enzymes suggest that the antimicrobial potency of these synthesized analogues could be due to enzyme inhibition via their favorable binding at the fluoroquinolone binding site at the GyrA subunit of DNA gyrase and/or the ParC subunit of topoisomerase-IV.

Free Radical Substitution Reactions of Sulfur Monochloride. A Limited Synthesis of Mercaptans

1973 ◽  
Vol 51 (20) ◽  
pp. 3366-3372 ◽  
Author(s):  
Dennis D. Tanner ◽  
Brian G. Brownlee
Keyword(s):  
Free Radical ◽  
Lithium Aluminum Hydride ◽  
Elemental Sulfur ◽  
Aluminum Hydride ◽  
Lithium Aluminum ◽  
Substitution Reactions ◽  
Sulfur Monochloride ◽  
Hydride Reduction ◽  
Abstraction Reaction ◽  
Radical Substitution

The photolysis of sulfur monochloride with a series of saturated aliphatic hydrocarbons yielded alkyl chlorides, di- and polysulfides, hydrogen chloride, and elemental sulfur. The free radical substitution reactions leading to the production of alkyl chloride and the di- and polysulfides were shown to proceed via a chlorine atom abstraction reaction. The major products, the di- and polysulfides could be transformed quantitatively, by lithium aluminum hydride reduction into their corresponding mercaptans. The reaction describes a simple free radical route to the synthesis of a variety of alkyl mercaptans.

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.

Preparation and Spectral Analysis of 3,3',4,4'-Tetrachloroazobenzene and the Corresponding Azoxy and Hydrazo Analogs

1979 ◽  
Vol 62 (4) ◽  
pp. 746-750
Author(s):  
M T Stephen Hsia ◽  
Charles F Burant
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Chromatographic Method ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Lithium Aluminum ◽  
Reverse Phase ◽  
High Pressure Liquid Chromatographic ◽  
Hydride Reduction ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic

Abstract An efficient preparation was developed for 3,3',4,4'-tetrachloroazobenzene and the corresponding azoxy and hydrazo derivatives, based on the lithium aluminum hydride reduction of 3,4-dichIoronitrobenzene. Batches were analyzed for purity by using a reverse phase high pressure liquid chromatographic method. All 3 compounds can be synthesized in gram quantities with 97–99% purity. Detailed mass, infrared, and nuclear magnetic resonance spectral analyses are presented.

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