Barbaloin, glycosides

Aloe latex is an active laxative. Its effect is due to anthraquinone glycosides, aloin A and B (formerly designated barbaloin). Glycosides are probably chemically stable in the stomach (under... 

C-Glycosides are typified by barbaloin, a component of the natural purgative drag cascara, but, as a group, the M-glycosides are perhaps the most important to biochemistry. Al-Glycosidic linkages are found in the nucleosides, components of DNA and RNA (see Section 14.1). In addition, nucleosides are essential parts of the structures of crucial biochemicals such as ATP, coenzyme A, NAD+, etc. The amine in these types of compound is part of a purine or pyrimidine base (see Section 14.1). 

N.A. Aloin isobarbaloin, aloeresin A, B, aloesin glycone, aloesone, emodin, chrysophanic acid, 1,8-dihydroxy-anthracene derivatives, barbaloin, anthaquinone glycosides.99-100 108 109 510-511 Purgative, eupeptic, and cholagogue effect. It is a laxative and cathartic. Juice from leaves used for cuts and other skin problems. 

The principal purgative activity originates from the cascarosides, the C-glycosides barbaloin and chrysaloin being less active when taken orally. As with the sennosides, the actual purgative... 

Aloin (= Barbaloin) (anthrone glycoside) Abeferox, A. perryi, A. vera (Liliaceae) [leaf], Frangula alnus, Frangula purshiana (Rhamnaceae) PS - eEF-2 [purgative]... 

Medicinal Aloes contains C-glycosides similar to those of Cascara as well as primary glycosides called Aloinosides and also various resins. The main constituent is Barbaloin. Pharmacopoeial-quality Cape Aloes must... 

While C-glycoside chemistry has recently attracted much attention, they were not invented by chemists. Many examples of C-glycosides have been isolated from nature. For example, in the structures represented in Figure 1.3.1 were isolated from Barbados aloe. These compounds, aloin A and aloin B, are collectively known as barbaloin make up the bitter and purgative principle of aloe.8-12... 

Koeppen" has reported that homoorientin, orientin, and barbaloin yield glycerol on oxidation with periodate, followed by reduction with sodium borohydride and acid hydrolysis. A similar result had been reported earlier for mangiferin, which is now known to be a C-glycosyl compound (see p. 360) and it is clear that this method cannot reliably differentiate C-glycosyl compounds and glycosides. 

In a later paper, Fairbairn and Simic described the cascarosides as primary glycosides of barbaloin and chrysaloin (11-deoxyaloin) and mentioned that about four have been identified. 

Occurrence. The sugar is encountered infrequently. Cathartic-acting glycosides (aloins) such as barbaloin, isobarbaloin, nataloin, and homo-nataloin from plants of the genus Aloe A. barbadensis) yield D-arabinose 39). The glycosidic union is very resistant to hydrolysis. The sugar occurs in the furanose modification as a constituent of the polysaccharide fraction of tubercle bacilli 40). 

Plants of the genus Aloe contain a reduced form of aloe-emodin as the C-glucoside of the corresponding anthrone, which is called aloin. Lemon yellow aloin is a mixture of two isomers. The major product (S)-aloin or (S)-P-D-glucopyranoside-aloe-emodin is referred to as aloin A (or barbaloin, 9-162), the (l )-isomer is aloin B (isobarbaloin). Related glycosides called aloinosides a and b contain a-L-rhamnopyranose bound by an O-glycosidic bond to the hydroxymethyl group at C-3. 

Commercial aloin is a concentrated form of aloe containing high concentrations of anthia-glycosides (mostly barbaloin). This commercial product is not pure aloin. 

Contains 6-10% (usually ca. 8%) anthragly-cosides as its active principles that consist primarily (60% or more) of C-glucosides (cascarosides) A, B, C, D, E, and F and barbaloin and chrysaloin), with minor concentrations of 0-glycosides (e.g., frangulin) also present. Other constituents include free anthraquinones (e.g., emodin, aloe-emodin. 

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