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Crude resins

After evaporation of the ether under reduced pressure, 1.525 g of the crude resinous base is obtained, which constitutes the required product in a crude and impure condition. [Pg.175]

Operculinic acids E (hexadecanoic acid, (115)-[(0-6-deoxy-a-L-mannopyranosyl-(1 4)-0-6-deoxy-a-L-mannopyranosyl-(1 4)-0-6-deoxy-a-L-mannopyranosyl-(1 2)-jS-D-glucopyranosyl)oxy]) and F (hexadecanoic acid, (115)-[(0-6-deoxy-a-L-mannopyranosyl-(1 4)-0-6-deoxy-a-L-mannopyranosyl-(1 4)-0-6-deoxy-a-L-mannopyranosyl-(1 2)-/i-D-xylopyranosyl)oxy]) were obtained by alkaline hydrolysis of the ether-soluble crude resin glycosides from the roots of Ipomoea... [Pg.92]

The methyl ester of operculinic acid E was obtained by basic hydrolysis and methylation of the crude resin glycoside mixture of 7. murucoides. Mumcoidins XII (53) and XIII (54) afford operculinic acid E as their oligosaccharide core. The lactonization site was placed at C-3 of the first rhamnose unit. These resin glycosides contain an esterifying residue that is composed of n-dodecanoic or (25)-methylbu-tyric acids at the C-2 or C-3 positions on the second rhamnose unit of the oligosaccharide core and (25)-methylbutyric acid at C-4 on the third rhamnose (30). [Pg.93]

Ono M, Kawasaki T, Miyahara K (1989) Resin Glycosides. V. Identification and Characterization of the Component Organic and Glycosidic Acids of the Ether-Soluble Crude Resin Glycosides ( Jalapin ) from Rhizoma Jalapae Brasiliensis (Roots of Ipomoea operculata). Chem Pharm Bull 37 3209... [Pg.148]

Resin acids. To obtain good mass spectra of resin acids it has previously been necessary to esterify the acids. Figure 9 shows a chromatogram of a crude resin sample from Pinus montana. The small peaks at the beginning of the chromatogram represents monoterpenes and the main... [Pg.316]

Agha Jari topped crude Gach Saran atmospheric residuum Kuwait and Lagomedio atmospheric residual 3 Jobo crude resin fraction asphaltene fraction Adriatic Sea atmospheric resid Gach Saran vacuum residuum... [Pg.187]

In all examples of the palladium-catalyzed telomerization discussed up till now, the nucleophile (telogen) can be considered renewable. The taxogens used (butadiene, isoprene), however, are still obtained from petrochemical resources, although butadiene could, in principle, also be obtained from renewable resources via the Lebedev process that converts (bio)-ethanol into 1,3-butadiene. Limited attention has been given in this respect to the great family of terpenes, as they provide direct access to renewable dienes for telomerization. In particular, those terpenes industrially available, which are derived mostly from turpentine, form an attractive group of substrates. Behr et al. recently used the renewable 1,3-diene myrcene in the telomerization with diethylamine, for instance [18]. The monoterpene myrcene is easily obtained from (3-pinene, sourced from the crude resin of pines, by pyrolysis, and is currently already used in many different applications. [Pg.92]

Podophyllum peltatum (may apple, or American mandrake) and P. emodi are. respectively, American and Himalayan plants, widely separated geographically but used in both places as cathartics in folk medicine (94). An alcoholic extract of the rhizome known as podophyllin was included in many pharmacopoeias for its gastrointestinal effects it was included in the U.S.P., for example, from 1820 to 1942. At about this time the beneficial effect of podophyllin, applied topically to benign tumors known as condylomata acuminata, was demonstrated clinically (96). This usage was not inspirational, given that there are records of topical application in the treatment of cancer by the Penobscot Indians of Maine and, subsequently, by various medical practitioners in the United States from the 19th century (96). The crude resinous podophyllin is an irritant and unpleasant mixture unsuited to systemic administration. [Pg.865]

The first chemical constituent was isolated from podophyllin in 1880 and named podophyllotoxin (97). A structure was proposed in 1932 and after some fine-tuning (98) was shown to be the lignan (60). As might be expected, the crude resin contains a variety of chemical types, including the flavonols quercetin and kaempferol (99). Although these other constituents undoubtedly have biological activity, it is the lignans that have received most attention and to which we shall devote the remainder of this section. [Pg.865]

Using a procedure similar to Preparation 4-1 a mixture of 1.2 gm of suliur. 4.0 gm of anhydrous sodium carbonate, and 3.3 gm of p-dichlorobenzene was heated in a similar manner to give 2.4 gm of a pale-yellow, crude resin which is purified in a similar fashion. After drying the recovery amoimts to 87-88% of the crude which is a white powder, brittle when cold, and fuses sharply at 255°C. The polymer corresponds to the empirical composition of (C6H4S12) with MW 35,000-70,000. [Pg.107]

While bulk or emulsion polymerization can also be used for the purpose, the commercial manufacture of polystyrene is mostly carried out in a solution process using a free-radical initiator. The solvent, typically ethylbenzene, used at a level of 2-30%, controls the viscosity of the solution. High-impact-grade polymer used in injection-molding and extrusion is modified with butadiene rubber incorporated during polymerization. The solvent and residual monomer in the crude resin is removed by flash evaporation or in a devolatilizing extruder (at about 225°C). Figure 2.9 is a schematic of the polymerization process. [Pg.102]

Tall oil tal, oi(9)l [part trans. of Gr Talldl, part trans. Swedish tallolja, fr. tall pine + olja oil] n. A generic name for a number of products from the manufacture of wood pulp by the alkah process sulfate or kraft process. To provide some distinction between the various products, designations are often applied in accordance with the process or composition, some of which are cmde tall oil, acid refined tall oil, distilled tall oil, tall oil fatty acids, and tall oil rosin. The following designations for tall oil shall be considered obsolete crude resinous hquid, finn oil, liquid resin, liquid rosin, resin oil, sulfate pitch, sulfate resin, sulfate rosin, Swedish pine oil, Swedish resin, Swedish rosin, Swedish rosin oil, Sylvie oil, talloel, tallol, Swedish oil, fluid resin, and Swedish olein. [Pg.951]

The LMZ S-47 crude was first examined for asphaltene and resin concentration. Pentane precipitation of asphaltenes resulted in 10.5 (wt) % concentration of these particles in the crude. Resin concentration was determined to be 27.0 (wt) %. [Pg.240]

Alternatively, epichlorohydrin and water are removed by distillation at temperatures up to 180°C under vacuum. The crude resin/salt mixture is then dissolved in a secondary solvent to facilitate water washing and salt removal. The secondary solvent is then removed via vacuum distillation to obtain the taffy-resin product. [Pg.2669]

From 1987 to 1989, China, the former Soviet Union, and Portugal contributed, respectively, with about 55%, 12%, and 10% of the total crude resin produced in the world [42]. Currently, China, Brazil, and Indonesia are the major world producers of pine gum resins [79]. [Pg.4046]

Noda N, Kobayashi H, Miyahara K, Kawasaki T (1988a) Resin glycosides. II Identification and characterization of the component organic and glycosidic acids of the crude resin glucoside from the seeds of Ipomoea muricata. Chem Pharm BuU 36 621-633... [Pg.578]

To a flask equipped with a dropping funnel, reflux condenser, and mechanical stirrer are added 188 gm (2.0 moles) of phenol and 2.0 ml of concentrated sulfuric acid. The flask is heated to 80°C, and while stirring 138 ml of 37% formaldehyde (1.7 moles) is added dropwise at such a rate to maintain this temperature. After the addition, the reaction mixture is refluxed for ly hr, and the water then removed by vacuum distillation to afford the crude resin. The resin is washed with fresh water to remove unreacted phenol. The solid is dissolved in acetone and dried over anhydrous magnesium sulfate. The absence of free phenol is checked by using the infrared spectral band at 14.6 ju. The resin is isolated as a fine white powder by evaporation of the acetone solution. [Pg.69]

Numerous members of the family of the Conifera contain large. quantities of resin, and an oil consisting almost entirely of terpenes, in well-characterised resin ducts in the wood. This is especially the case with the various species, of pine. The exudation from the wood, an oleo-resin, is often known as crude turpentine. Oil of turpentine, or, as it is generally called, turpentine or turps, is the oil obtained by distilling this, leaving the crude resin or rosin behind. [Pg.9]

Gum rosin is obtained from tapped pine resin from living pine trees. Pine trees bleed crude resin when they are cut. In a rather labor-intensive operation, this crude resin is collected from the tapped trees and processed. Gum rosin and turpentine are obtained from this crude resin. Sometimes the gum rosins, which are composed of abietic acid, are used directly in rubber compounds as tackiflers. These gum rosins are sometimes chemically modified through either hydrogenation (to improve their aging properties) or esterification for use in rubber. The turpentine is sometimes processed further to separate out the S-pinene for polymerization into polyterpene resins for use as a rubber tackifier. [Pg.37]

Tall oil rosin is a byproduct from the fractionation of tall oil, which is a byproduct of the kraft paper pulping process. Since the gathering of crude resin is rather labor intensive, tall oil rosins have substituted somewhat for the gum rosins in developed countries where labor costs are higher. Sulfate pulp turpentine is also obtained from this kraft pulp digestion process. [Pg.37]

Labdanum resin absolute through alcohol extraction of the crude resin. [Pg.160]


See other pages where Crude resins is mentioned: [Pg.9]    [Pg.201]    [Pg.700]    [Pg.83]    [Pg.90]    [Pg.802]    [Pg.60]    [Pg.1709]    [Pg.700]    [Pg.700]    [Pg.245]    [Pg.230]    [Pg.579]    [Pg.579]    [Pg.956]    [Pg.184]    [Pg.9]    [Pg.815]    [Pg.255]   
See also in sourсe #XX -- [ Pg.229 , Pg.230 , Pg.237 ]




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