Stereochemical studies. VI. Stereoselective synthesis of trans-fused octahydroindene-1-carboxylic acids

1980 ◽  
Vol 33 (1) ◽  
pp. 101 ◽  
Author(s):  
M Galteri ◽  
PH Lewis ◽  
S Middleton ◽  
LE Stock
Keyword(s):  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Good Yield ◽  
Stereoselective Synthesis ◽  
Carboxyl Group ◽  
Derivatives Of ◽  
Acyl Derivatives

The trans-fused octahydroindene-1-carboxylic acid (9) having a pseudo- axial carboxyl group is formed in good yield on oxidation of 2-acyl derivatives of trans-fused octahydronaphthalen-1(2H)-one. On epimerization it yields the pseudo-equatorial isomer (3) which is structurally related to the gibberellic acids.

Isocarbostyrils. II. The Conversion of 2-Methyl-4-acyl-5-nitroisocarbostyrils to 2-Substituted Indole-4-carboxylic Acids

1971 ◽  
Vol 49 (17) ◽  
pp. 2797-2802 ◽  
Author(s):  
D. E. Horning ◽  
G. Lacasse ◽  
J. M. Muchowski
Keyword(s):  
Sulfuric Acid ◽  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Alkaline Hydrolysis ◽  
Mannich Reaction ◽  
Reductive Cyclization ◽  
Acid Catalyzed ◽  
Acid Anhydrides ◽  
Hydrolysis Of ◽  
Derivatives Of

The sulfuric acid catalyzed acylation of 2-methyl-5-nitroisocarbostyril with carboxylic acid anhydrides gave the corresponding 4-acylated derivatives 3, which underwent reductive cyclization to 2-substituted derivatives of 4-methyl-1,3,4,5-tetrahydropyrrolo[4.3.2.de]isoquinolin-5-one (4). Alkaline hydrolysis of the six-membered lactam in 4 was accompanied by a retro-Mannich reaction to produce 2-substituted indole-4-carboxylic acids in about 40 % overall yield from 3.

Derivate des Benzo[1.3]dioxols, 431 Über Benzo [1.3] dioxolcarbonsäuren / Derivatives of 1,3-Benzodioxoles, 43 1,3-Benzodioxolecarboxylic Acids

1978 ◽  
Vol 33 (7-8) ◽  
pp. 465-471
Author(s):  
Franz Daliacker ◽  
Volker Mues ◽  
In-O Kim
Keyword(s):  
Carboxylic Acid ◽  
Methyl Ester ◽  
Benzoic Acid ◽  
Myristic Acid ◽  
Good Yield ◽  
Acid Ester ◽  
Acid Methyl Ester ◽  
Acid Methyl ◽  
Derivatives Of

Abstract We describe the possibilities of formation and preparation of the “natural” 1,3-benzodioxolecarboxylic acids 1, 2, 4, 6 b, and 7, already mentioned in literature. Myristic acid (3e) was prepared in good yield from 3-methoxy-4,5-dihydroxy-benzoic acid ester (3c) , which could be easily made from 3-methoxy-2,3-carbonyldioxy-benzoic acid methylester (3b). Myristicic acid methylester (3d) could be subjected to methylation and hydrolysis leading to 3e without any difficulties. 4.6-dimethoxy-1,3-benzodioxole-5-carboxylic acid (5b) was prepared in good yields by oxidation of 4,6-dimethoxy-1,3-benzodioxole-5-aldehyde (5a). 5.7-dimethoxy-1,3-benzodioxole-carboxylic acid (13f), one of the “unnatural” 1,3-benzodioxolecarboxylic acids, derivatives of o-ipiperonylic acid (8), was prepared from 5-amino-7-methoxy-1,3- benzodioxole-4carboxylic acid methyl ester (13b) by diazotisation, elimination of nitrogen, methylation, and hydrolysis. A comparison of our measured pkA-values showed the strongest acidity belonging to 5,6-dimethoxy-1,3-benzodioxole-4-carbocylic acid (11).

Photochemical reactions of azo compounds. X. Photochemical properties of azobenzene-2-carboxylic acids

1967 ◽  
Vol 20 (5) ◽  
pp. 929 ◽  
Author(s):  
CP Joshua ◽  
GE Lewis
Keyword(s):  
Hydrogen Bonding ◽  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Intramolecular Hydrogen Bonding ◽  
Photochemical Reactions ◽  
Azo Compounds ◽  
Neutral Compounds ◽  
Methyl Derivatives ◽  
Intramolecular Hydrogen ◽  
Derivatives Of

Two chloro and two methyl derivatives of azobenzene-2-carboxylic acid have been found to yield the corresponding derivatives of benzo[c]cinnoline-4- carboxylic acid in good yields when irradiated in 98% sulphuric acid. The question of intramolecular hydrogen bonding in relation to the properties of azobenzene-2-carboxylic acids is discussed. Infrared absorption spectra of the neutral compounds have provided confirmation of internal hydrogen bonding. Attempts to prepare the cis isomers of these azo compounds have been unsuccessful.

Thiohydantoins. II. Thiohydantoins Derived from Aspartic and Glutamic Acids

1952 ◽  
Vol 5 (4) ◽  
pp. 721
Author(s):  
JM Swan
Keyword(s):  
Acetic Anhydride ◽  
Carboxylic Acids ◽  
Ammonium Thiocyanate ◽  
Derivatives Of ◽  
Isomeric Pairs ◽  
Acyl Derivatives

N-Acyl derivatives of the &carboxylic acids, aspartic and glutamic acids, yield the corresponding anhydrides when heated with acetic anhydride in the presence or absence of ammonium thiocyanate. In general these anhydrides form isomeric pairs of amides and anilides, and only one of each pair can be converted into the corresponding 2-thiohydantoin. The anhydrides from N-phenylacetyl- and N-p-nitro-benzoylglutamic acids, and N-acetylaspartic acid have been regarded hitherto as oxazolones.

scholarly journals Design of two series of 1:1 cocrystals involving 4-amino-5-chloro-2,6-dimethylpyrimidine and carboxylic acids

2018 ◽  
Vol 74 (9) ◽  
pp. 1007-1019 ◽  
Author(s):  
Ammaiyappan Rajam ◽  
Packianathan Thomas Muthiah ◽  
Raymond John Butcher ◽  
Jerry P. Jasinski ◽  
Jan Wikaira
Keyword(s):  
Carboxylic Acid ◽  
Hydrogen Bonds ◽  
Carboxylic Acids ◽  
Halogen Bond ◽  
Single Point ◽  
Carboxyl Group ◽  
Aminobenzoic Acid ◽  
Halogen Bonds ◽  
Large Cage ◽  
Acta Cryst

Two series of a total of ten cocrystals involving 4-amino-5-chloro-2,6-dimethylpyrimidine with various carboxylic acids have been prepared and characterized by single-crystal X-ray diffraction. The pyrimidine unit used for the cocrystals offers two ring N atoms (positions N1 and N3) as proton-accepting sites. Depending upon the site of protonation, two types of cations are possible [Rajam et al. (2017). Acta Cryst. C73, 862–868]. In a parallel arrangement, two series of cocrystals are possible depending upon the hydrogen bonding of the carboxyl group with position N1 or N3. In one series of cocrystals, i.e. 4-amino-5-chloro-2,6-dimethylpyrimidine–3-bromothiophene-2-carboxylic acid (1/1), 1, 4-amino-5-chloro-2,6-dimethylpyrimidine–5-chlorothiophene-2-carboxylic acid (1/1), 2, 4-amino-5-chloro-2,6-dimethylpyrimidine–2,4-dichlorobenzoic acid (1/1), 3, and 4-amino-5-chloro-2,6-dimethylpyrimidine–2-aminobenzoic acid (1/1), 4, the carboxyl hydroxy group (–OH) is hydrogen bonded to position N1 (O—H...N1) of the corresponding pyrimidine unit (single point supramolecular synthon). The inversion-related stacked pyrimidines are doubly bridged by the carboxyl groups via N—H...O and O—H...N hydrogen bonds to form a large cage-like tetrameric unit with an R 4 2(20) graph-set ring motif. These tetrameric units are further connected via base pairing through a pair of N—H...N hydrogen bonds, generating R 2 2(8) motifs (supramolecular homosynthon). In the other series of cocrystals, i.e. 4-amino-5-chloro-2,6-dimethylpyrimidine–5-methylthiophene-2-carboxylic acid (1/1), 5, 4-amino-5-chloro-2,6-dimethylpyrimidine–benzoic acid (1/1), 6, 4-amino-5-chloro-2,6-dimethylpyrimidine–2-methylbenzoic acid (1/1), 7, 4-amino-5-chloro-2,6-dimethylpyrimidine–3-methylbenzoic acid (1/1), 8, 4-amino-5-chloro-2,6-dimethylpyrimidine–4-methylbenzoic acid (1/1), 9, and 4-amino-5-chloro-2,6-dimethylpyrimidine–4-aminobenzoic acid (1/1), 10, the carboxyl group interacts with position N3 and the adjacent 4-amino group of the corresponding pyrimidine ring via O—H...N and N—H...O hydrogen bonds to generate the robust R 2 2(8) supramolecular heterosynthon. These heterosynthons are further connected by N—H...N hydrogen-bond interactions in a linear fashion to form a chain-like arrangement. In cocrystal 1, a Br...Br halogen bond is present, in cocrystals 2 and 3, Cl...Cl halogen bonds are present, and in cocrystals 5, 6 and 7, Cl...O halogen bonds are present. In all of the ten cocrystals, π–π stacking interactions are observed.

Directed biosynthesis of novel derivatives of echinomycin by Streptomyces echinatus. I. Effect of exogenous analogues of quinoxaline-2-carboxylic acid on the fermentation

1984 ◽  
Vol 30 (4) ◽  
pp. 439-450 ◽  
Author(s):  
D. Gauvreau ◽  
M. J. Waring
Keyword(s):  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Time Course ◽  
Biologically Active ◽  
Aromatic Acids ◽  
Gram Positive Bacteria ◽  
Directed Biosynthesis ◽  
Derivatives Of ◽  
Carbonyl Chromophores

Streptomyces echinatus A8331 cultured on a maltose minimal salts medium normally produces a single antibiotic, echinomycin (quinomycin A), containing two quinoxaline-2-carbonyl chromophores. Echinomycin is powerfully active against experimental tumours and can be assayed by its activity against Gram-positive bacteria. Grown in the presence of aromatic carboxylic acids related to quinoxaline, S. echinatus responds in favourable circumstances by incorporating the added material into analogues of the natural antibiotic having replacement chromophores. Both mono- and bis-substituted derivatives are formed. With quinoline-2-carboxylic acid as precursor, large quantities of analogues are produced, and the time course of synthesis, extraction, purification, assay, and characterization of the derivatives are described. Twenty-two other aromatic acids have been tested as potential substrates for antibiotic analogue biosynthesis. Half of them did not significantly affect growth and echinomycin production. Five appeared to stimulate antibiotic synthesis, while the remainder proved inhibitory. New biologically active antibiotics were detected in cultures supplemented with 7-chloroquinoxaline-2-carboxylic acid; 1,2,4-benzo-as-triazine-3-carboxylic acid; thieno[3,2-b]pyridine-5-carboxylic acid; and 6-methylquinoline-2-carboxylic acid.

Characterization of Carboxylic Acids: Identification of Their Anilide Derivatives by X-ray Diffractometry

1976 ◽  
Vol 30 (2) ◽  
pp. 204-209 ◽  
Author(s):  
Kenneth J. Garska
Keyword(s):  
Mass Spectrometry ◽  
Carboxylic Acid ◽  
Qualitative Analysis ◽  
Carboxylic Acids ◽  
Isomeric Form ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Patterns ◽  
Derivatives Of

In order to extend the data available for the characterization of carboxylic acids, an x-ray diffraction technique has been used for the identification of their anilide derivatives. This technique often makes possible the identification of carboxylic acids that cannot be examined readily by other techniques such as gas chromotography and mass spectrometry. Reference x-ray diffraction patterns have been obtained for the anilide derivatives of 32 carboxylic acids containing up to 18 carbon atoms. Detailed descriptions are given for obtaining and qualitatively using the x-ray diffraction patterns of these anilides. The x-ray diffraction patterns of these anilides are unique; even closely related acids which differ only in isomeric form produce anilide derivatives which exhibit different and characteristic x-ray diffraction patterns. In the qualitative analysis of single or multicomponent carboxylic acid-containing mixtures, this x-ray diffraction technique is used either alone or with infrared spectrometric techniques.

A useful method for preparation of carboxylic acids from terminal alkynes

1983 ◽  
Vol 61 (10) ◽  
pp. 2423-2424 ◽  
Author(s):  
Suzanne R. Abrams
Keyword(s):  
Acetic Acid ◽  
Sulfuric Acid ◽  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Chain Length ◽  
Good Yield ◽  
Terminal Alkynes ◽  
Terminal Acetylenes ◽  
Long Chain ◽  
Acetic Acids

Substituted acetic acids can be prepared in good yield (50–80%) from terminal acetylenes of the same chain length. The alkyne is first converted to the thiophenyl ether, which is treated without purification with mercuric sulfate in acetic acid and 2 N sulfuric acid affording the carboxylic acid. The method is particularly useful in the synthesis of long chain ω-hydroxyalkanoic acids.

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