Resin Acids. VIII. Reaction of Levopimaric Acid with Acetylenic Dienophiles1,2

1966 ◽  
Vol 31 (6) ◽  
pp. 1800-1803 ◽  
Author(s):  
Werner Herz ◽  
R. C. Blackstone ◽  
M. G. Nair
Keyword(s):  
1970 ◽  
Vol 35 (10) ◽  
pp. 3338-3342 ◽  
Author(s):  
Werner. Herz ◽  
Robert C. Ligon ◽  
Hideo. Kanno ◽  
Walter H. Schuller ◽  
Ray V. Lawrence
Keyword(s):  

1987 ◽  
Vol 65 (1) ◽  
pp. 7-14 ◽  
Author(s):  
William A. Ayer ◽  
John B. Macaulay

The fungus Armillariamellea (Vahl ex. Fr.) Kummer is responsible for severe losses in timber and fruit production. The metabolites isolated when certain strains of this fungus are grown in liquid culture have been identified as diterpenoid acids possessing the abietane (1) and pimarane (2) skeletons. These compounds, known collectively as resin acids, have not been reported previously from a fungal source. In addition to the resin acids dehydroabietic acid (3), pimaric acid (4), isopimaric acid (5), and sandaracopimaric acid (6), three additional acids, levopimaric acid endo-peroxide (7), 7-oxodehydroabietic acid (9), and 7-oxo-15-hydroxydehydroabietic acid (10) were obtained. On one occasion three orange pigments, austocystin F (11), averufin (12), and averufanin (13), all previously known fungal metabolites, were isolated.


1967 ◽  
Vol 32 (10) ◽  
pp. 2992-2998 ◽  
Author(s):  
Werner Herz ◽  
Robert C. Blackstone ◽  
M. G. Nair
Keyword(s):  

2021 ◽  
Author(s):  
Wu-Ji Lai ◽  
Jia-Hao Lu ◽  
Rui Jiang ◽  
Lei Zeng ◽  
Ai-qun Wu ◽  
...  

Abstract Acrylopimaric acid is considered one of the possible substitutes for petroleum-based polymeric monomers, which is an important industrial product. Resin acids were isomerized to form levopimaric acid(4), which reacted with acrylic acid to synthesize isomers of acrylopimaric acid. Density functional theory calculation was used to investigate the reaction mechanisms with seven reaction paths in five different solutions. The values of ΔG were sorted from highest to lowest by levopimaric acid(4), neoabietic acid(3), palustric acid(2), and bietic acid(1). From the perspective of dynamics, the energy barrier in the isomerization of palustric acid(2) to levopimaric acid(4) was the lowest, whereas the highest energy barrier was the isomerization of neoabietic acid(3) to levopimaric acid(4) in the same solution. The addition reaction of levopimaric acid(4) and acrylic acid(5) to acrylopimaric acid c(8) was the optimal reaction path dynamically. However, ΔG of acrylopimaric acid c(8) was higher than that of acrylopimaric acid d(9). In general, the rates of isomerization reactions for rosin resin acids and addition reaction for acrylopimaric acid in water were higher than those in other solvents. HOMO-LUMO and ESP were analyzed for 8 kinds of molecules. For acylpyimaric acid, the non-planar six-memed ring and the C-C double bonds were easily attacked by nucleophile, while the non-planar six-memed ring and the carboxyl group are easily reacted with electrophiles. The highest electrostatic potential of the eight molecules is located at H of the carboxyl group, while the highest electrostatic potential is located at C-O double bond of the carboxyl group.


1972 ◽  
Vol 50 (14) ◽  
pp. 2224-2229 ◽  
Author(s):  
Ray F. Severson ◽  
Walter H. Schuller

The hot tube pyrolysis of dehydroabietic acid (1) at 400–500 °C was found to produce as major products the three possible A-ring olefins (19-norabieta-4,8,11,13-tetraene (2); 19-norabieta-4(18),8,11,13-tetraene (3); and 19-norabieta-3,8,11,13-tetraene (4)) resulting from the elimination of the carboxylate moiety. The i.r., n.m.r., u.v., and mass spectrum of each olefln was obtained and discussed. The pyrolysis of abietic acid (7) and levopimaric acid (8) under identical conditions was found to yield A-ring olefins; to isomerize to yield varying mixtures of palustric, 7, and neoabietic acids; to dehydrogenate to yield 1; and to eliminate propylene to form deisopropyldehydroabietic acid (15). A mechanism to explain the formation of 15 from the dienoic resin acids is given.


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