Chinese folk medicine

Copper hydride species, notably Stryker s reagent [Ph3PCuH]6, are capable of promoting the conjugate reduction of a,( >-unsalurated carbonyl compounds [42], Taking advantage of this trustworthy method, Chiu et al. demonstrated in 1998 an intramolecular reductive aldol reaction in the synthesis of novel terpenoid pseudolaric acids isolated from Chinese folk medicine (Scheme 28) [43]. Two equivalents of [Ph3PCuH]6 enabled cycli-zation of keto-enone 104 to provide the bicyclic diastereomers 105 (66%) and 106 (16%). The reaction also was applied to the transformation of 107... 

Hirsutine (2-795), which belongs to the corynanthe subgroup of the indole alkaloids, was isolated from the plant Uncaria rhynchophylla MIQ and used for the preparation of the old Chinese folk medicine Kampo [397]. It is of pharmacological interest as it shows a strong inhibitory effect on the influenza A virus (subtype H3N2) with an EC50 = 0.40-0.57 pg ml. which is about 11- to 20-fold higher than that of the clinically used ribavirin [398]. 

The hypocrellins (7-9) are Class B perylenequinones that have also been the subject of much investigation due to their biological activity, having been used in Chinese folk medicine for the treatment of vitiligo, psoriasis, and other diseases for... 

Cucurbitine (47) is the active principle from the seeds of Cucurbita moschata Duch., which are used in Chinese folk medicine. The structure of this unique a-amino acid was established through a combination of chemical and spectroscopic techniques (81, 82). A single-crystal X-ray analysis of the perchlorate of cucurbitine has confirmed the original hypothesis and has established the absolute configuration of 47 (83). 

A new medicine that seems to be promising in this field is artimisinine (19) isolated from Artimisia annua. Extracts of this plant have been known for centuries in Chinese folk medicine under the name of Qinghaosu or Qinghao. For solubility reasons and hydrolysis stability, artimisinine is converted via the dihydro compound into water-soluble artesunate or oil soluble artemether and arteether (Scheme 5.12) [43]. 

Quinghaosu is the latest fundamental discovery in this area and is a heterocyclic compound that does not have a nitrogen atom in its structure. It is taken from a Chinese folk medicine. It is isolated from the plmt Artemisia annua. It is amazing that this compound, which is completely different than the other drugs described in this chapter in terms of structure, exhibits the exact same therapeutic effect. The main interest in quinoghaosu is based on the fact that it is active against resistant forms of malaria caused by P falciparum, and even its cerebral forms. Synonyms of this drug are artemisine, artemisinin, and others. 

Fukai, T. et al.. Phenolic constituents of Glycyrrhiza species. 17. Three isoprenoid-substituted isoflavans, gancaonins X-Z, from Chinese folk medicine Tiexin Gancao (root xylems of Glycyrrhiza species). Natural Medicines, 48, 203, 2004. 

The use of sulfoximines in the syntheses of optically active compounds has been reported [429]. A remarkable ketone methylcnation with optical resolution was realized. A highly selective diastereofacial addition of an enantiopure sulfoximine to a racemic ketone, chromatographic separation of the two diastereoisomers and reductive cleavage yielded both enantiomers of p-panasinsene [430], isolated from the root of ginseng, a herb used in Chinese folk medicine. 

Only four inhibitors of AChE have been approved as therapeutic drugs for combating dementia diseases. The very first is tacrine or Cognex [Figure 2] from Parke-Davis8 and the second is aricept from Eisai [Japan] and Pfizer [U.S.].9 A third inhibitor available is huperzine A, a "nootropic" agent isolated from a Chinese folk medicine and used by Chinese for centuries to improve memory.10 Other known reversible AChE inhibitors... 

The alkaloids hirsutine (1) and its 3or-epimer dihydrocorynantheine (2a) belong to the corynanthe group of indole alkaloids. They have been isolated from the plant Uncaria rhynchophylla MIQ, which was used for the preparation of the old Chinese folk medicine kampo . Nowadays, 1 and related compounds attract great attention in medicine because of their growth inhibition of the influenza A subtype H3N2 virus. With an EC50 value of 0.40-0.57 ig/mL 1 has shown itself to be 10-20 times more active than the clinically used drug ribavirine (3).1,2 Furthermore, 1 is known for its antihypertensive and antiarrhythmic activity.3... 

The hexahydropyrrolo[2,l-a]isoquinoline alkaloid crispine A was isolated in 2002 from Carduus crispus ]15]. Extracts of this plant have been applied in Chinese folk medicine for the treatment of colds, stomach ache, and rheumatism moreover they inhibit the growth of several human cancer cell lines. The useful biological activities induced a strong interest over the last few years in the synthesis of this alkaloid [7,16]. 

The mixture of constituents [e.g., normacusine B (2), affinisine (8), Na-methylpericyclivine (41), voachalotine (64)] present in Peschiera van heur-ckii from the tropical rain forest in Bolivia is known for its alleged leishmani-cidal and bactericidal activity (37). Like many quaternary alkaloids, the major quaternary alkaloid from Strychnos angolensis, 11-methoxymacusine A (76), shows muscle-relaxant activity (187). The crude mixture of nine alkaloids present in Ervatamia yunnanensis is used in Chinese folk medicine for the treatment of hypertension (176). One of these alkaloids is a sarpagine derivative [voachalotine (64)]. 

Studies on the health benefits of pu-erh tea are quite scarce. Recently, a few reports describing the hypolipidemic and antiobesity effects of pu-erh tea have appeared. - Meanwhile, Chinese folk medicine has described several health benefits for this beverage, but the experimental and clinical evidence for these benefit effects is incomplete. Additional investigations should be carried out in order to confirm these claims. 

Various plants used in traditional medicine contain significant amounts of PPG For example, different species of Scrophularia genus, have been traditionally used for several skin inflammatory ailments. The leaves of species of Buddleja have been applied topically as a poultice or lotion for the healing of wounds and ulcers. Ballota nigra is commonly used for their neurosedative activity and Pedicularis sp. are a Chinese folk medicinal h erb, f ound e specially i n T ibet, u sed to t reat m alignant s ores, collapse, exhaustion, and relieves uneasiness of body and mind. 

From the fruits of Gleditsia japonica, which have been used in Japanese and Chinese folk medicine as a diuretic and expectorant, seven saponins (gleditsiasaponins B, C, Dj, D2, E, G and I) had been isolated. The structural elucidation of these saponins have been carried out by the chemical degradations, enzymatic hydrolysis and C-NMR spectra, and characterized as 3, 28-0-bisglycosides of echinocystic acid acylated with monoterpene carboxylic acid [46-49]. 

Bemeuxia thibetica Decne, which is spread in the Southwest of China, is used as Chinese folk medicine for curing cough due to pathogenic wind-K Id factors, overstrain, asthma and dyspea, and wound[l].We have reported sterols, triterpenes and flavones from the EtOAc part of EtOH extracts[2,3,4].We now report the triterpenoid saponins isolated from the leaves of this plant. 

I eudolaric acids. Diterpenoids from the bark of Pseudolarix kaempferi, also known as Tujinpi in Chinese folk medicine, traditionally used against fungal skin infections. Besides the in vivo antifungal activity P. show in vitro cytotoxicity against several human tumor cell lines, the most effective sP. B (CjsHjgOg, Mr 432.46, cryst., mp. 165-167°C). 

The application of antibiotics for the treatment of diseases is not new. [30] In Chinese folk medicine, the healing properties of curd cheese with mouldy beans had been known for at least 2,500 years. From records we know that the Romans and Egyptians used mouldy bread for the treatment of diseases. The peoples of Sudan and Nubia also used antibiotics from a very early date on. Fluorescence spectra of bones from those times show strong agreement with the spectra from bones of patients, who have been treated with tetracyclines. 

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