Chondodendron

Initially, neuromnscnlar jnnction blockers were isolated from curare, the extract of which is produced from South American plants Strychnos and Chondodendron. Today, synthetic compounds as well as tnbocnrarine, an alkaloid isolated from curare, are used as antidepolarizing or cnrare-like drags, which are called antidepolarizing or competitive blockers. 

Tubocurarine Tubocurarine, 7, 12 -dihydroxy-6,6 -dimethoxy-2,2,2, 2 -tetramethyl-tubocuraranium dichloride (15.1.1), is synthesized from an aqueous extract of the Chondodendron plant [1-6]. 

Curare is obtained from various members of the menisperm or moonseed family, particularly from the vines of Chondodendron tomentosum and other members of the Chondodendron genus as well as from various species of Strychnos (Figure 26.1). 

Curare or South American arrow poison varies in composition among Indian tribes. However, the bark of one or more species of Strychnos apparently is always used in its preparation. Strychnos castelnaei Weddell, S. toxifera Bentham, S. Crevauxii G. Planchon, and Chondodendron tomentosum Ruiz Pavon are commonly employed. 

FIGURE 26.1 Left, Chondodendron tomentosum from which curare is derived right, the Amazonian rain forest, the habitat of the plant. 

Curare is a natural product isolated from trees and bushes of the Strychnos and Chondodendron geni. The active principle (d-tubocurarine) is a water-soluble and heat-stable alkaloid that can be extracted, heated, and concentrated to produce a pasty residue containing a high concentration of curare. This extract has been used for centuries in South America as an arrow poison. Curare is not absorbed from the gastrointestinal tract, nor can it penetrate the blood-brain barrier. In order for curare to produce its effects, it must be injected into the body. 

The chloride of an alkaloid, (+ )-tubocurarine. It may be obtained from extracts of the stems of Chondodendron tomento-sum (Menispermaceae). 

Choline bromide succinate, 998 Choline chloride, 466 Choline chloride carbamate, 427 Choline chloride succinate, 998 Choline citrate, 466 Choline dihydrogen citrate, 466 Choline salicylate, 965 Choline theophyllinate, 1011 Cholinesterase activity, assay kit, 1171 quantification in serum, 23 test for inhibition of, 6 Chondodendron tomentosum, 1057 Chromatographic performance, evaluation of, 189 Chromatography, adsorption, 204... 

Chemical/Pharmaceutical/Other Class Toxic alkaloid (o-tubocurare) found in South American woody vines including Strychnos toxifera, S. castelnaei, S. crevauxii, and Chondodendron tom-entosum... 

Chondodendron tomentosum Ruiz and Pavon (Menispermaceae)] 141,142] Cyclea barbaia (Wall.) Miers (Menispermaceae)] 143]... 

Chondodendron tomentosum Ruiz and Pavon (Menispennaceae)[141,142,200] Chondendron toxicoforum (Wedd.) Kruk. et Mold. (Menispermaceae)[20l]... 

Chondodendron limaciifolium (Diels) Moldenke (Menispermaceac)[3l2] Chondodendron microphylum (Eichl.) Moldenke (Menispermaceae)] 146] Chondodendron plaiiphyllum Miers (Menispermaceae)] 146]... 

The only naturally occurring alkaloid of this small group is (+)-norcycleanine (124)[which is really 7 -O-demethylcycleanine). This alkaloid is not as widely distributed as its R,K diastereoisomer (-)-norcycleanine (125). The (+)-isomer has only been isolated from two plants Isolona hexaloba (Annonaceae) and Stephania cepharantha (Menispermaceae), neither of which are a source of the (-)-isomer (which was found in four Menispermaceous genera Chondodendron, Cyclea, Epinelrum, and Synclisia. The base tetra-O-demethylcycleanine (128a) has been reported, but data was not available. 

There are four alkaloids in the (-)-curine family (-)-curine (133), cycleacurine (134), O,O-dimethylcurine (135), and 12 -O-methyIcurine (140). These alkaloids differ in the position of various phenolic hydroxy groups and methoxy groups among the C(7), C(12), and C(6 ) positions. (-)-Curine (133) has been isolated from six genera of the Menispermaceae including Chondodendron, Cissampelos. Cyclea, Paracyclea, Pleogyne, and Stephania. In addition, this... 

The two nonquatemary alkaloids of this small subgroup are chondocurine (130) and nor-N(,-chondocurine (230), the latter being the N(2 ) nor- derivative of the former. Chondocurine (also called chondrocurine) has been isolated from Chondodendron tomentosum and 2 species of Cyclea, all three plants being of the family Menispermaceae. The nor-base 230 and chondocurine have both been isolated from what is only described as Peruvian curare. 

The alkaloids of this small subgroup seem to be solely distributed within Menispermaceaous plants, particularly of the genus Chondodendron. 

Two closely related alkaloids from this group are curicycleatjenine (400) and curicycleatjine (401), compounds that contain a methylenedioxy function at C(S)/C(6). These two alkaloids differ only in the nature of the C(12) function, whereas in the former it is methoxy group and in the latter a hydroxy group. These alkaloids have only been isolated from Cyclea atjehensis (Menispermaceae). Hayatidine (136), an alkaloid of Cissampelos pareira (Menispermaceae), is a diastereoisomer of 12 -O-methylcurine (140). (-)-Tubocurarine (143), a diastereoisomer of (+)-tubocurarine (142), has only been isolated from Chondodendron lomentosum (Menispermaceae). 

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