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Min Xu

Bio: Min Xu is an academic researcher from Chinese Academy of Sciences. The author has contributed to research in topics: Panax notoginseng & Medicine. The author has an hindex of 25, co-authored 122 publications receiving 1832 citations. Previous affiliations of Min Xu include Nanjing Normal University & Griffith University.


Papers
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TL;DR: In this paper, a chiral trifluoromethyl quaternary carbon center of dihydroquinazoline was constructed by an asymmetric Mannich reaction and chiral recognition.
Abstract: The highly enantioselective construction of a quaternary carbon center of dihydroquinazoline by an asymmetric Mannich reaction and chiral recognition are described The key transformation was to establish the chiral trifluoromethyl quaternary carbon center by a diamine-Bronsted acid-catalyzed enantioselective and regioselective Mannich reaction of a methyl ketone and 4-trifluoromethyldihydroquinazoline An unusual phenomenon of self-discrimination of enantiomers in hydrogen-bonded dimers was observed A valuable intermediate was transformed into the enantiopure HIV reverse transcriptase inhibitor DPC 083 (>999 ee) simply by reduction of the carbonyl group and elimination of the hydroxy group in hexamethylphosphoric tramide (HMPA)

76 citations

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TL;DR: Chemical investigation led to the identification of two new 8-C substituted flavan-3-ols, puerins A and B, and two known cinchonain-type phenols, epicatechin-[7,8-bc]-4alpha-(4-hydroxyphenyl)-dihydro-2(3H)-pyranone and cinchesonain Ib.
Abstract: Pu-er tea is a special treated fermented tea produced from crude green tea, which is prepared from the leaves of Camellia sinensis var. assamica. It is a traditional beverage having been used in China, particularly the southern areas, for a long time. Chemical investigation led to the identification of two new 8-C substituted flavan-3-ols, puerins A (1) and B (2), and two known cinchonain-type phenols, epicatechin-[7,8-bc]-4 alpha-(4-hydroxyphenyl)-dihydro-2(3"-pyranone (3) and cinchonain lb (4), together with other seven known phenolic compounds, 2,2',6,6'-tetrahydroxydiphenyl (5), (-)-epicatechin-8C-beta-D-glucopyranoside (6), (-)-epicatechin (EC) (7), (-)-epigallocatechin (EGC) (8), (+/-)-gallocatechin (GC) (9), gallic acid (10), and myricetin (11), in addition to caffeine (12). Their structures were determined by spectroscopic methods. The compounds 1-5, which might be formed in the postfermentative process of Pu-er tea, were isolated from tea and theaceous plants for the first time.

74 citations

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TL;DR: How long-term common soil management practices affect the abundance and type of ARGs and MGEs in two very different soil environments, one aerobic and the other primarily anaerobic is shown.
Abstract: Different fertilization and cropping systems may influence short- and long-term residues of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) in soil. Soils from dryland (peanut) and paddy (rice) fields, which originated from the same nonagricultural land (forested), were treated with either chemical fertilizer, composted manure, or no fertilizer for 26 years before sampling, which occurred one year after the last applications. ARGs and MGEs were investigated using highly parallel qPCR and high-throughput sequencing. Six of the 11 antibiotics measured by LC–MS/MS were detected in the manure applied soil, but not in the nonmanured soils, indicating their source was from previous manure applications. Compared to the unfertilized control, manure application did not show a large accumulation of ARGs in either cropping system but there were some minor effects of soil management on indigenous ARGs. Paddy soil showed higher accumulation of these ARGs, which corresponded to higher microbial bi...

71 citations

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TL;DR: In this paper, HPLC analyses on saponin composition of processed notoginseng were conducted, which revealed that, during the steaming process, the five main ginsenosides (ginsenosides Rg(1), Rb-1, Rd, and Re, and notogsenoside R-1) decreased gradually and some other new saponins were formed.

67 citations

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TL;DR: It was concluded that the hydrological cycle had obviously changed and that more soil water was transferred into the GW since the aquiclude changed due to climate warming, which resulted in increased water storage.

61 citations


Cited by
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TL;DR: This review covers the literature published in 2014 for marine natural products, with 1116 citations referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms.

4,649 citations

Journal ArticleDOI
TL;DR: This review summarizes the chemistry, biosynthesis and occurrence of the compounds involved, namely the C6-C3-C6 flavonoids-anthocyanins, dihydrochalcones, Flavan-3-ols, flavanones, flavones, Flavonols and isoflavones, and the mechanisms underlying these processes are discussed.

1,728 citations

01 Dec 2013
TL;DR: This paper found that the most intensive glacier shrinkage is in the Himalayan region, whereas glacial retreat in the Pamir Plateau region is less apparent, due to changes in atmospheric circulations and precipitation patterns.
Abstract: Glacial melting in the Tibetan Plateau affects the water resources of millions of people. This study finds that—partly owing to changes in atmospheric circulations and precipitation patterns—the most intensive glacier shrinkage is in the Himalayan region, whereas glacial retreat in the Pamir Plateau region is less apparent.

1,599 citations

01 Dec 2007

1,121 citations