SOLVENT FREE OXALIC ACID CATALYZED SYNTHESIS …
Short-chain dicarboxylic acids are of great importance in thegeneral metabolism and up to n=3 they cannot be considered as lipids since their watersolubility is important. The simplest of these intermediates is oxalic acid (n=0), theothers are malonic (n=1), succinic (n=2) and glutaric (n=3) acids.
The other lipid members of the group found in natural products or from synthesis have a"n" value from 4 up to 21.
Oxalic acid mediated synthesis of WO 3·H 2O …
Suberic acid, nonanedioic acid (and its mono-unsaturated derivative:2-nonenedioic acid), decanoic acid (and its mono-unsaturated derivative:2-decenedioic acid) are present in honey () and are of special interest becausethey have long been recognized as part of the pheromone system of the honeybee (). They are producedin the mandibular glands of the queen and the worker honeybees, they regulatetheir activities in the hive.
It was shown that all these dicarboxylic acids are formed during the dryingprocess of and that thedetermination of these decomposition products may be of value in determining theage of old samples.
The higher weight dicarboxylic acids (n=10 to 21) are found in different plant lipids, particularly in what was named erroneously (triglycerides containing C20, 21, 22 and 23 dicarboxylic acids besides normal fatty acids) from the sumach tree (Rhus sp.). Among them, Thapsic acid (n=14) was isolated from the dried roots of the Mediterranean "deadly carrot", Thapsia garganica (Umbelliferae), but others, as Brassylic acid (n=11), were prepared chemically from different sources.
Brassylic acid can be produced chemically from erucic acid by ozonolysis but also by microorganisms () from . This diacid is produced on a small commercial scale in Japan for the manufacture of fragrances.
A review on the applications and the industrial biotechnology of these moleculeshas been released by Kroha K ().
A large survey of the dicarboxylic acids present in Mediterranean nuts revealed unusual components (). A total of 26 minor acids (from 2 in pecan to 8% in peanut) were determined : 8 species derived from butanedioic acid, likely in relation with photosynthesis, and 18 species with a chain from 5 to 22 carbon atoms.
Higher weight acids (>C20) are found in present at vegetal surfaces (outer bark, root epidermis). C16 to C26
Some of the metabolites are toxic like glycolic acid (metabolic acidosis) and oxalates which may induce kidney and CNS toxicity In vitro, MCA blocks the cell energy supply in an as yet incompletely resolved manner, leading to a gradual decrease in ATP generation and in protein synthesis.