Studies On Chemical Constituents

Qingqianliu is the species belong to the genus Cyclocarya of Juglandaceae. It is the only species in the genus Cyclocarya, Chinese endemic plant, widely distributed in the south of Yangtze region. According to ’zhongguozhongyaoziyuanzhiyao’its leaves, bark, roots can be used as medicine. Qingqianliu has the effect of clearing heat, detoxifying detumescence and analgesic, so it can be used in the treatment of dense tinea. Because of its sweet taste, the effect of clearing heat, and decreasing blood pressure, its leaves is made into tea, known as sweet tea, or ShenCha.By using a variety of chromatographic techniques and spectroscopic methods, this dissertation investigated chemical constituents of the Cholesterol-lowering activity EtOAc-soluble portions of the 95% EtOH extract from the leaves of Cyclocarya paliurus (Batal) Iljinsk. Compounds (1-24) were isolated and their structures were determined, including seven 3,4-secodammarane-type triterpenoid saponins, they are (23E)-(12R,20S)-20-hydroxy-25-methoxy-3,4-secodammara-4(28),23-diene-3-oic acid-12-O-β-D-quinovopyranoside (1), (23E)-(12R,20S)-20-hydroxy-25-methoxy-3, 4-secodammara-4(28),23-dien-3-oic acid ethyl ester-12-O-β-D-quinovopyranoside (2), (23E)-(12R,20S)-20-hydroxy-25-methoxy-3,4-secodammara-4(28),23-dien-3-oic acid-12-O-α-L-arabinopyranoside(3), (23E)-(12R,20S)-20-hydroxy-25-methoxy-3, 4-secodammara-4(28),23-dien-3-oic acid ethyl ester-12-O-α-L-arabinopyranoside (4), (23E)-(12R,20S)-20-hydroxy-3,4-secodammara-4(28),23,25-trien-3-oic acid-12-O-α-L-arabinopyranoside (5), (12R,20S,24S)-20,24-dihydroxy-3,4-secodammara-4(28),25-dien-3-oic acid-12-O-α-L-arabinopyranoside (6) and pterocaryoside B(13); one 3,4-secodammarane-type triterpenoid:(23E)-(12R,20S)-12,20-dihydroxy-3,4-secodammara-4(28),23,25-trien-3-oic acid methyl ester (12); three dammarane-type triterpenoid saponin, they are:(23E)-(20S)-(3α,12β)-20-hydroxy-dammara-23,25-dien-12-O-α-L-arabinopyranosyl-3-O-α-L-arabinofuranoside (7), (23E)-(20S)-(3α,12β)-20-hydroxy-dammara-23,25-dien-12-O-β-D-quinovopyranosyl-3-O-α-L-arabinofuranoside (8), (23E-(20S)-(3α,12β)-20-hydroxy-25-methoxy-dammara-23-en-3-O-β-D-quinovopyranosyl-12-O-α-L-arabinopyranoside (9); two epoxydammarane-type triterpenoid saponins they are:(20S,24R)-(3α,12β)-20, 24-epoxydammara-25-ol-12-O-β-D-quinovopyranosyl-3-O-(5-O-acetyl)-α-L-arabinofura noside (10) and (20S,24R)-(3α,12β)-20,24-epoxydammara-25-ol-12-O-β-D-quinovopyranosyl-3-O-a-L-arabinopyranoside (11); six pentacyclic triterpenes, among them two ursane-type:ursolic acid(14) and 2a-hydroxyursolic acid(15), three oleanane-type:oleanolic acid(16), arjunolic acid(17) and cyclocaric acid B(18), one taraxerane-type:taraxerol(19); one megastigmane norterpenoid: 6,9-dihydroxy-7-megastigmen-3-one(20); one apocarotenoid:loliolide(21); one flavonoid glycosides:kaempferol-3-O-α-L-rhamnopyranosyl(22); one sterols: β-sitosterol(23); one long chain fatty alcohol esters:Behenic acid monoglyceride (24). Among them, compounds 1-12 are new, and compounds 13,19-22 were isolated from this genus for the fist time.In addition, the compounds isolated from it were evaluated against several human cancer cell lines and were not active (IC50>10μM). They were screened for inhibitory activities against a-glucosidase, lipase, DPP-IV, and aldose reductase, respectively. These compounds showed weak activities at the concentration of 10-5M.