Five new flavonoids were isolated from the aerial parts of Bidens pilosa L. var. vadiata Sch.-Bip.. Their structures were established on the basis of spectroscopic methods.
From the dried leaves of I. eriocalyx, three new 6,7-seco- ent-kaurane diterpenoids epi-eriocalyxin A (2), maoecrystal N (3) and maoecrystal O (4) were isolated. Meanwhile, the structure of a known constituent eriocal...From the dried leaves of I. eriocalyx, three new 6,7-seco- ent-kaurane diterpenoids epi-eriocalyxin A (2), maoecrystal N (3) and maoecrystal O (4) were isolated. Meanwhile, the structure of a known constituent eriocalyxin A was revised.展开更多
3-Methoxy-, 3, 5-dimethoxy-, and 3-phenyl-4-hydroxyacetophenones suffered alkyl carbonyl C-C bond scission to yield 4-hydroxybenzoate esters and 4-isopropenylphenols under standard conditions of ethylene ketal formati...3-Methoxy-, 3, 5-dimethoxy-, and 3-phenyl-4-hydroxyacetophenones suffered alkyl carbonyl C-C bond scission to yield 4-hydroxybenzoate esters and 4-isopropenylphenols under standard conditions of ethylene ketal formation; the latter underwent in situ dimerization, cyclization, and rearrangement to give substituted indanols. The isopropenylphenol derived from 3,5-ditertbutyl-4-hydroxyacetophenone did not dimerize but condensed with its precursor to yield a substituted diphenylpropanone. 3-nitro-, 3,5-dinitro-, and 3,5-dibromo-4-hydroxyacetophenones on the other hand reacted normally to give ethylene ketals in good yields.展开更多
IN vitro and in vivo experiments show the protective effects of glial cell line-derived neu-rotrophic factor (GDNF) on dopaminergic (DA) neurons are potent and relatively specif-ic. However, GDNF protein is not small ...IN vitro and in vivo experiments show the protective effects of glial cell line-derived neu-rotrophic factor (GDNF) on dopaminergic (DA) neurons are potent and relatively specif-ic. However, GDNF protein is not small enough to pass blood-brain-barrier (BBB).展开更多
THE electrochemical and/or photochemical active organic molecules have attracted much atten-.tion due to their potential applications in the field of molecular electronics. The azobenzenederivatives have been widely s...THE electrochemical and/or photochemical active organic molecules have attracted much atten-.tion due to their potential applications in the field of molecular electronics. The azobenzenederivatives have been widely studied as typical systems, owing to their reversible trans-cis iso-merization and reduction/oxidation reactions (see fig. 1 (a) ). We have studied the char-acteristic photochromic and electrochemical behavior of azobenzene Langmuir-Blodgett mono-展开更多
文摘Five new flavonoids were isolated from the aerial parts of Bidens pilosa L. var. vadiata Sch.-Bip.. Their structures were established on the basis of spectroscopic methods.
文摘From the dried leaves of I. eriocalyx, three new 6,7-seco- ent-kaurane diterpenoids epi-eriocalyxin A (2), maoecrystal N (3) and maoecrystal O (4) were isolated. Meanwhile, the structure of a known constituent eriocalyxin A was revised.
文摘3-Methoxy-, 3, 5-dimethoxy-, and 3-phenyl-4-hydroxyacetophenones suffered alkyl carbonyl C-C bond scission to yield 4-hydroxybenzoate esters and 4-isopropenylphenols under standard conditions of ethylene ketal formation; the latter underwent in situ dimerization, cyclization, and rearrangement to give substituted indanols. The isopropenylphenol derived from 3,5-ditertbutyl-4-hydroxyacetophenone did not dimerize but condensed with its precursor to yield a substituted diphenylpropanone. 3-nitro-, 3,5-dinitro-, and 3,5-dibromo-4-hydroxyacetophenones on the other hand reacted normally to give ethylene ketals in good yields.
文摘IN vitro and in vivo experiments show the protective effects of glial cell line-derived neu-rotrophic factor (GDNF) on dopaminergic (DA) neurons are potent and relatively specif-ic. However, GDNF protein is not small enough to pass blood-brain-barrier (BBB).
文摘THE electrochemical and/or photochemical active organic molecules have attracted much atten-.tion due to their potential applications in the field of molecular electronics. The azobenzenederivatives have been widely studied as typical systems, owing to their reversible trans-cis iso-merization and reduction/oxidation reactions (see fig. 1 (a) ). We have studied the char-acteristic photochromic and electrochemical behavior of azobenzene Langmuir-Blodgett mono-
