Resin Acids. II. The Structure of Neoabietic Acid

1948 ◽  
Vol 70 (1) ◽  
pp. 339-343 ◽  
Author(s):  
George C. Harris ◽  
Thomas F. Sanderson
Keyword(s):  
2010 ◽  
Vol 5 (11) ◽  
pp. 1934578X1000501 ◽  
Author(s):  
Ahmet C. Gören ◽  
Gökhan Bilsel ◽  
Alp Hakan Öztürk ◽  
Gulaçtı Topçu

The compositions of colophony resins obtained from Pinus brutia Ten trees by three different methods (acid paste, carved hole and scraping) from Ayvacık, Gökova and Kemalpaşa in Turkey were analyzed by capillary GC-MS. The main components were the monoterpenes α-pinene, β-pinene, and Δ3-carene, and the diterpenic resin acids palustric, abietic, kaur-9(11)-16-en-18-oic and neoabietic acid. The synthetic colophony resins exhibited similar contents to those of the natural resins obtained from the Gökova and Kemalpaşa regions of Turkey. However, colophony resins from Ayvacık exhibited only half the diterpenic acid content as those of the Gökova and Kemalpaşa resins. Out of the three techniques, the carved hole method caused rather different percentages in the constituents of the essential oils.


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.


1992 ◽  
Vol 22 (4) ◽  
pp. 588-592 ◽  
Author(s):  
Jarmo K. Holopainen ◽  
Jaana Tuhkalainen ◽  
Pirjo Kainulainen ◽  
Heli Satka

Polyphagous Lygus (Heteroptera: Miridae) bugs, which have one of the widest documented host-plant ranges, have accepted nursery-grown conifer seedlings as host plants only recently. One explanation for this adaptation to the conifer nursery environment could be the increased attractiveness of conifer seedlings due to herbicide treatments. In three laboratory experiments, we tested whether atrazine treatments (2 or 4 kg•ha−1) affected shoot chemistry of pine seedlings and the feeding and oviposition behaviour of the European tarnished plant bug, Lygusrugulipennis Popp. Shoot growth of the pine seedlings was decreased by the atrazine treatment (2 kg•ha−1) in only one experiment. The number of feeding lesions caused by Lygus bugs and the number of eggs laid per seedling were not affected by herbicide treatments, nor was the proportion of seedlings damaged. Concentrations of total amino acids were not affected by the herbicide in any of the experiments. In one experiment, the level of lysine was increased in the atrazine treatment. Terpenes and resin acids were analysed only in one experiment, and total concentrations of these defence compounds were not affected by atrazine. Dominant monoterpenes were α-pinene and 3-carene, the latter varying strongly between individual seedlings. Abietic acid and neoabietic acid were the dominant abietane and pimarane resin acids. The results suggest that applications of atrazine are not likely to reduce the resistance of pine seedlings to Lygus bugs. Herbicides may have an indirect effect by reducing the availability of alternative host plants for bugs. Other potential causes for increased numbers of Lygus bugs on nursery-grown conifer seedlings are discussed.


1985 ◽  
Vol 15 (1) ◽  
pp. 92-96 ◽  
Author(s):  
Rolf Gref ◽  
Anders Ericsson

One-year-old Pinussylvestris (L.) seedlings were wounded at the stem base by stripping off stem bark pieces of approximately 10 mm in length and covering about 50% of the stem circumference. The seedlings were thereafter planted out in the field or in a climate chamber. The field experiment was repeated on four different planting dates. Wounded and control seedlings were successively harvested for gas chromatographic determination of changes in resin acid concentrations of the bark surrounding the wounded area. Independent of planting date, wounded seedlings were found to have higher concentrations of total resin acids than corresponding controls. The most important quantitative changes in resin acids were observed for isopimaric, levopimaric + palustric, dehydroabietie, abietic, and neoabietic acid. In wounded seedlings the concentration of dehydroabietic acid showed the most significant increase, both in the field and in climate chamber experiments. This increase was rapid and appeared within 1 week in the field and within 3 days in the climate chamber. The other resin acids identified showed a somewhat similar variation pattern, but the differences were not as distinct as for dehydroabietic acid. These wound-induced rapid changes in resin acid concentrations could be important for resistance to pathogens.


2006 ◽  
Vol 34 (6) ◽  
pp. 1209-1214 ◽  
Author(s):  
B. Hamberger ◽  
J. Bohlmann

Diterpene resin acids, together with monoterpenes and sesquiterpenes, are the most prominent defence chemicals in conifers. These compounds belong to the large group of structurally diverse terpenoids formed by enzymes known as terpenoid synthases. CYPs (cytochrome P450-dependent mono-oxygenases) can further increase the structural diversity of these terpenoids. While most terpenoids are characterized as specialized or secondary metabolites, some terpenoids, such as the phytohormones GA (gibberellic acid), BRs (brassinosteroids) and ABA (abscisic acid), have essential functions in plant growth and development. To date, very few CYP genes involved in conifer terpenoid metabolism have been functionally characterized and were limited to two systems, yew (Taxus) and loblolly pine (Pinus taeda). The characterized yew CYP genes are involved in taxol diterpene biosynthesis, while the only characterized pine terpenoid CYP gene is part of DRA (diterpene resin acid) biosynthesis. These CYPs from yew and pine are members of two apparently conifer-specific CYP families within the larger CYP85 clan, one of four plant CYP multifamily clans. Other CYP families within the CYP85 clan were characterized from a variety of angiosperms with functions in terpenoid phytohormone metabolism of GA, BR, and ABA. The recent development of EST (expressed sequence tag) and FLcDNA (where FL is full-length) sequence databases and cDNA collections for species of two conifers, spruce (Picea) and pine, allows for the discovery of new terpenoid CYPs in gymnosperms by means of large-scale sequence mining, phylogenetic analysis and functional characterization. Here, we present a snapshot of conifer CYP data mining, discovery of new conifer CYPs in all but one family within the CYP85 clan, and suggestions for their functional characterization. This paper will focus on the discovery of conifer CYPs associated with diterpene metabolism and CYP with possible functions in the formation of GA, BR, and ABA in conifers.


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