Chemical Constituents Of Psammophyte Artemisia Halodendron And Their Anti-complement Activities

Artemisia halodendron Turcz.ex Bess.,a typical sandy shrub of the genus Artemisia in the family Asteraceae,is widely distributed in Northeast,North and Northwest of China.A.halodendron has been used as Chinese folk medicine to treat chronic bronchitis,asthma,and rheumatoid arthritis.Previous phytochemical and pharmacological investigations revealed the presence of flavonoids,phenols,and coumarins isolated from A.halodendron and exhibited anti-inflammation and anti-liver injury.In order to search for more structurally unique active components and to develop the potential medicinal value of this herbal resource,the chemical constituents from A.halodendron.and their anti-complementary activities were investigated.All the compounds(1-29)were isolated from the n-BuOH fraction of A.halodendron using silica-gel column chromatography and MPLC,respectively.The chemical structures of the isolated compounds were determined by NMR spectra.As a result,twenty-nine compounds were identified,including twelve flavonoids:eriodectyol(1),sakuranetin(2),eriodicty ol-7-methyl ether(3),padmatin(4),quercetin(5),7,4’-di-O--methylquercetin(6),quercetin-5-O-β-D-glucopyranoside(7),quercetin-5-O-[α-L--rhamnopyranosyl-(1→6)]-β-D-glucopyranoside(8),3,3’-di-O-m ethyl quercetin(9),isorhamnetin-3-O-β-D-glucopyranoside(10),isorhamnetin-3-O-β-D-rutinoside(11),and tamarixetin-5-O-β-D-glucoside(12),seven phenols:4-(1-hydroxylethyl)--phenol-1-O-β-D-glucopyranoside(13),picein(14),2-methoxy-4-propenyl)--pheny-β-D-glucoside(15),6-O-caffeoyl-α-D-glucopyranoside(16),6-O-caffeoyl-β--D-glucopyranoside(17),3,4-O-dicaffeoylquinic acid methyl ester(18),and 3’,5’-di-C-β-glucopyranosylphloretin(19),two alkynes:3(R)-deca-4,6,8-triyne-1,3--diol(20),and 3S,8S-dihydroxydec-9-en-4,6-yne-1-O-β-D-glucopyranoside(21),two sesquiterpenes:negunfurol(22)and schensianol A(23),two diterpenoids:(1S,3E,5R,7E,9R,11E)-9-O-β-D-glucopyanosyl-3,7,11-cembradiene-5-ol(24)and(1S,2S,3E,5R,7E,9R,11E)-9-O-β-D-glucopyanosyl-3,7,11-cembradiene-2,5-diol(25),two lignans:(-)-syringaresinol-4-O-β-D-glucopyranoside(26),7(R),8(S)-3,3’--dimethoxy-4,9,9’-trihydroxy-4’,7-epoxy-5’,8-lignan-4,9-bis-O-β-D-gluopyranoside(27),and two carbohydrate-based compounds:(Z)-3-hexenyl-β-D-glucopyranoside(28)and isopentyl-β-D-glucopyranoside(29).Among them,compounds 8,16,17,19,24,25 and 27 were isolated from the family Asteraceae for the first time,compounds 1,2,4,7,9,11,13,18,20-23,26,28 and 29 had not been reported in the genus Artemisia and compounds 6 and 12 were firstly reported from A.halodendron.Furthermore,the anti-complementary activities of compounds were evaluated on CP and AP of the complement system in vitro.The results revealed that compounds 18 and 20 showed significantly anti-complementary activities with CH50 values of 0.31 ± 0.08 mM and 0.50 ± 0.09 mM nearly to positive drug,and compounds 4,7,8,9,and 12 also exhibited anti-complementary activities with CH50 values of 0.82～1.04 mM in the classical pathway.Base on the above results,compounds 4,7,8,9,12,18 and 20 could be plausible candidates for developing potent anti-complementary agents,and A.halodendron could be promising as potential therapeutic agents for diseases related to immunological diseases in the future.