PREPARATION OF CAFFEIC AND DIHYDROCAFFEIC ACIDS BY METHODS SUITABLE FOR INTRODUCTION OF C14 INTO THE β-POSITION

1959 ◽  
Vol 37 (1) ◽  
pp. 1431-1438 ◽  
Author(s):  
A. C. Neish

3,4-(Dibenzyloxy)-benzoyl chloride (m.p. 95°) was prepared from the corresponding acid, and reduced to 3,4-(dibenzyloxy)-benzaldehyde (m.p. 86°) by Rosenmund's method. The over-all yield of this aldehyde was 52%, based on the barium carbonate used for preparation of the acid. The aldehyde was debenzylated by hydrogen bromide in acetic acid, and the protocatechualdehyde thus obtained was condensed with malonic acid, to give caffeic acid. Condensation of 3,4-(dibenzyloxy)-benzaldehyde with malonic acid gave 3,4–(dibenzyloxy)-cinnamic acid (m.p. 206–208°) which was converted to dihydrocaffeic acid by catalytic hydrogenation. The over-all yields of caffeic and dihydrocaffeic acids were 36% and 39%, respectively, based on barium carbonate. Protocatechuic acid was readily obtained by hydrogenolysis of 3,4-(dibenzyloxy)-benzoic acid; the yield was 70% based on carbonate.

1959 ◽  
Vol 37 (12) ◽  
pp. 1431-1438 ◽  
Author(s):  
A. C. Neish

3,4-(Dibenzyloxy)-benzoyl chloride (m.p. 95°) was prepared from the corresponding acid, and reduced to 3,4-(dibenzyloxy)-benzaldehyde (m.p. 86°) by Rosenmund's method. The over-all yield of this aldehyde was 52%, based on the barium carbonate used for preparation of the acid. The aldehyde was debenzylated by hydrogen bromide in acetic acid, and the protocatechualdehyde thus obtained was condensed with malonic acid, to give caffeic acid. Condensation of 3,4-(dibenzyloxy)-benzaldehyde with malonic acid gave 3,4–(dibenzyloxy)-cinnamic acid (m.p. 206–208°) which was converted to dihydrocaffeic acid by catalytic hydrogenation. The over-all yields of caffeic and dihydrocaffeic acids were 36% and 39%, respectively, based on barium carbonate. Protocatechuic acid was readily obtained by hydrogenolysis of 3,4-(dibenzyloxy)-benzoic acid; the yield was 70% based on carbonate.


1968 ◽  
Vol 106 (2) ◽  
pp. 507-514 ◽  
Author(s):  
Keith Moore ◽  
P. V. Subba Rao ◽  
G. H. N. Towers

Ammonia-lyase activity for l-phenylalanine, m-hydroxyphenylalanine and l-tyrosine was demonstrated in cell-free extracts of Sporobolomyces roseus. Cultures of this organism converted dl-[ring−14C]phenylalanine and l-[U−14C]tyrosine into the corresponding cinnamic acid. Tracer studies showed that these compounds were further metabolized to [14C]protocatechuic acid. Benzoic acid and p-hydroxybenzoic acid were intermediates in this pathway. Washed cells of the organism readily utilized cinnamic acid, p-coumaric acid, caffeic acid, benzoic acid and p-hydroxybenzoic acid. Protocatechuic acid was the terminal aromatic compound formed during the metabolism of these compounds. The cells of S. roseus were able to convert m-coumaric acid into m-hydroxybenzoic acid, but the latter compound, which accumulated in the medium, was not further metabolized. 4-Hydroxycoumarin was identified as the product of o-coumaric acid metabolism by this organism.


Author(s):  
Jenan Mohammed Ubaid ◽  
Abeer Fauzi Al-Rubaye ◽  
Imad Hadi Hameed

Methanolic extract of bioactive compounds of Trogoderma granarium was assayed. GC-MS analysis of Trogoderma granarium revealed the existence of the Pentanoic acid , 1,1-dimethylpropyl ester , (1H)-Pyrimidinone , 5-chloro-4,6- diphenyl, Cyclobutanemethanol , α-methyl- , Nitro-2-methyl-1,3-propanediol , Hydroxylamine ,O-(2-methylpropyl)- , Uridine , 2',3'-O-(phenylmethylene)- ,Acetic acid ,2-benzoylthio-,2-oxo-2-phenylethyl ester , methylpropyl)- , Uridine , 2',3'-O-(phenylmethylene)- , 5'-(4-methylbenzenesulfo , Indolinol , 1-benzoyl-, Benzeneethanol , β-methyl-,(s)- , Acetic acid ,2-benzoylthio-,2-oxo-2-phenylethyl ester , Phenacyl thiocyanate , Deoxy-L-ribose-2,5-dibenzoate , Methenamine , Alanine , N-methyl-n-propargyloxycarbonyl-, decyl ester , Benzoyl chloride , Thiophene-2-ol , benzoate , Ethanone , -(5- nitrotetrazol-2-yl)-1-phenyl- , 2,5-Dimethylhexane-2,5-dihydroperoxide , Benzamide , N-(3-benzylthio-1,2,4-thiadiazol- 5-yl)- , Methyl p-(2-phenyl-1-benzimidazolyl)benzoate , Methyl-2-phenoxyethylamine , Pentaborane(11) , cis-Methoxy- 5-trans-methyl-1R-cyclohexanol , Nitro-1-phenyl-3-(tetrahydropyran-2-yloxy)propan-1-one , cis-Methoxy-5-transmethyl-1R-cyclohexanol. Trogoderma granarium produce many important secondary metabolites with high biological activities.


1959 ◽  
Vol 37 (12) ◽  
pp. 1439-1446 ◽  
Author(s):  
A. C. Neish

A simplified technique was developed for carbonation of Grignard reagents or organolithium compounds, with C14O2 generated from barium carbonate. 3,4-(Dibenzyloxy)-bromobenzene was treated with n-butyl lithium in ether and then with C14O2 to give 3,4-(dibenzyloxy)-benzoic acid-carboxyl-C14. The yield was 74% based on barium carbonate. 2,6-Dichlorobenzoic acid-carboxyl-C14 (yield 77%) and 3,5-dichlorobenzoic acid-carboxyl-C14 (yield 76%) were prepared from the corresponding dichlorobromobenzenes by a similar sequence of reactions. Attempts to synthesize 2,4- and 2,5-dichlorobenzoic acids by this route gave poor yields of unidentified acids, from which the expected products could not be isolated.


1933 ◽  
Vol 8 (5) ◽  
pp. 447-449 ◽  
Author(s):  
Steward Basterfield ◽  
James W. Tomecko

The ionization constants of p-nitrophenylacetic and phenylmalonic acids have been determined from conductivity data. The value of K for p-nitrophenylacetic acid at 25 °C. is 1.04 × 10−4, about twice that of phenylacetic acid. The nitro group in the nucleus has not as powerful an effect on the ionization when the COOH group is in the side chain as it has when both nitro group and COOH are in the nucleus. K for p-nitrobenzoic acid is six times as great as K for benzoic acid. K for phenylmalonic acid is 2. 77 × 10−3 as compared with 1.6 × 10−3 for malonic acid.


1992 ◽  
Vol 70 (5) ◽  
pp. 1492-1505 ◽  
Author(s):  
Peter Yates ◽  
Magdy Kaldas

Treatment of 2-norobornene-1-carboxylic acid (7) with one equivalent of methyllithium in ether followed by a second molar equivalent after dilution with tetrahydrofuran gave 1-(norborn-2-en-lyl)ethanone (10) and only a trace of the tertiary alcohol 11. Reaction of 7 with formic acid followed by hydrolysis gave a 4:3 mixture of exo-3- and exo-2-hydroxynorbornane-1-carboxylic acid (16 and 17), whereas oxymercuration–demercuration gave only the exo-3-hydroxy isomer 16. Oxidation of 16 and 17 gave 3- and 2-oxonorbornane-1-carboxylic acid (27 and 29), respectively. Oxymercuration–demercuration of 10 gave exclusively 1-(exo-3-hydroxynorborn-1-yl)ethanone (30), which was also prepared by treatment of 16 with methyllithium in analogous fashion to that used for the conversion of 7 to 10. Oxidation of 30 gave 1-(3-oxonorborn-1-yl)ethanone (1). Dehydrobromination of exo-2-bromonorbornane-1-acetic acid and dehydration of 2-hydroxy-norbornane-2-acetic acid derivatives gave 1-(norborn-2-ylidene) acetic acid derivatives to the exclusion of norborn-2-ene-1 -acetic acid derivatives. Treatment of exo-5-acetyloxy-2-norobornanone (52) with ethyl bromoacetate and zinc gave ethyl exo-5-acetyloxy-2-hydroxynorbornane-(exo- and endo-2-acetate (53 and 54). Reaction of 53 with hydrogen bromide gave initially ethyl endo-3-acetyloxy-exo-6-bromonorbornane-1-acetate (59), which was subsequently converted to a mixture of 59 and its exo-3-acetyloxy epimer 61. Catalytic hydrogenation of this mixture gave a mixture of ethyl endo- and exo-3-acetyloxynorbornane-1 -acetate (62 and 63). Basic hydrolysis of this gave a mixture of the corresponding hydroxy acids, 70 and 71; the former was slowly converted to the latter at pH 5. Oxidation of the mixture of 70 and 71 gave 3-oxonorbornane-1-acetic acid (72). Treatment of the mixture with methyllithium as for 16 gave a mixture of 1-(endo- and exo-3-hydroxynorborn-1-yl)-2-propanone (73 and 74), which was oxidized to 1-(3-oxo-norborn-1-yl)-2-propanone (2). Reaction of exo-2-hydroxynorbornane-1-acetic acid lactone (75) with methyllithium in ether gave (1-(exo-2-hydroxynorborn-1-yl)-2-propanone (76), which on oxidation gave the 2-oxo isomer 78 of 2.


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