Copalic acid

Kopolkerinde. /. copalche (or copalchi) bark. Kopal-lack, m. copal varnish, -luftlack, m. airproof copal varnish, -mattlack, m. dull copal varnish, -bl, n. copal oil. -saure, /, copalic acid. 

The fruit oil of the leguminous tree Pterodon pubescens contains geranylgeraniol (3) and its terminal epoxide (98). This terminal epoxide is highly lethal to the cercariae of Schistosoma mansoni, the causative agent of schistosomiasis (Gilbert, 1977). Other unsaturated diterpenes such as dehy-droabietic acid, agathic acid, and copalic acid prevent cercar-ial penetration. 

Labda-8( 17), 13E-dien-15-al, l-oxo-ent-Labda-8( 17), 13E-dien-15-al, 2a-hydroxy- n/-Labda-8( 17), 13E-dien-15-oic acid, en -[E-Copalic acid]... 

IManila Copal. The Manilas are collected in Indonesia and the Philippines. They are soluble in alcohols and ketones, and insoluble in hydrocarbons and esters. The resins soften between 81—90°C and have acid numbers of 110—141. Principal uses are in coatings and varnishes. 

Pontia.na.k. This resin is a copal and is similar to the alcohol-soluble Manilas. It is partially fossilized, so it melts at a higher temperature. Softening points range from 99—135°C, and acid numbers from about 112—120. Pontianak [9000-14-0] is used in specialty coatings and adhesives. 

Kopal-baum, m. copal tree, -brecher, m. copal disintegrator. -fimis, m. copal varnish, -harz, -gummi, n. copal resin, copal, -in-saure, /. copalinic acid. 

Copals, sometimes referred to as immature amber, originate from Africa, Asia or central American countries and derive from the Araucariaceae and Leguminosae families. Polymerised communic acid and agathic acid are found as the main compounds in these fossil resins. The extreme hardness of copal results from polymers of resin acids such as ozoic acid, an enantiomer of communic acid that can polymerize and thus enable fossilization [86]. They are still commonly used today for varnishing and protecting wood. 

Lae resin is very difficultly soluble in alcohol, though, like copal, it may be completaly teken up by this advent. Like most of the other resins, It has a strong affinity for bases, with which it forms definite compounds. Dilute hydrochloric acid and acetic acid dissolve the rosin freely, but not the strong sulphurto acid. Borax solutions with the aid of heat also take it up. The portion soluble in alcohol has a specific gravity of 1-139, IIhvekdokbeN found it to be a compound of several rosins, namely—... 

The Amherstiae copals have been a rich source of labdane and rearranged labdane diterpenoids. The full description of oliveric acid (7) isolated from one of these, Daniellia oliveri, has appeared. ... 

The carbonates, sulphates, and borates are decomposed. The sulphides of the alkalies and alkaline earths are decomposed while the sulphides of arsenic, antimony, molybdenum, zinc, cadmium, tin, iron, lead, copper, mercury, and palladium are not attacked. Cobalt sulphate is not attacked, while the sulphates of the alkalies and alkaline earths are attacked and dissolved. Alkali tungstates, ammonium arsenite and arsenate, copper arsenite, ammonium magnesium arsenate, ammonium molybdate and vanadate, potassium cyanide and ferrocyanide are decomposed. Paraffin is not attacked shellac, gum arabic, gum tragacanth, copal, etc., are decomposed. Celluloid is slowly attacked. Silk paper, gun cotton, gelatin, parchment are dissolved. M. Meslans 22 has studied the esterification of alcohol by hydrofluoric acid. 

Analytical pyrolysis has been proven a very useful tool in the identification of resins used for artistic objects [16,17], The pyrograms of Manila copal, colophony, Venice turpentine, elemi, shellac, dammar, sandarac, and mastic were obtained and used as fingerprints for these materials. Manila copal, colophony, and Venice turpentine were characterized by the presence of a degradation compound from abietic acid (as the source of these resins is from species of Coniferae), probably methyl-isopropylnaphthalene. Elemi has a characteristic peak for elemicine, shellac showed a series of fatty acids, dammar showed the presence of sesquiterpenes (see Section 6.3), sandarac was characterized by a phenolic compound, totarol, and mastic was also identified by specific sesquiterpenes [17]. 

Yellowish to yellowish-brown pieces of various sizes con-dtoidal fracture odorless and tasteless, Hard copals are almost insol in usual solvents soft copals are partly sol in alcohol, chloroform or glacial acetic acid both copals after having been fused are sol in oil turpentine and linseed oil. 

Amber, colophonium, copals, mastix, and shellac develop a beautifully blue color when in contact with ether mixed with ammonium molybdate (0.1 g in 5 ml concentrated sulfuric acid) and ammonia. Thinius reports a number of additional color reactions for the above natural resins, but these do not permit unambiguous identification in each case, especially since phenolic resins produce similar colors. 

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