https://pubs.rsc.org/en/content/articlepdf/2019/NP/C8NP00092A

Marine natural products.

Dietary phenolics: chemistry, bioavailability and effects on health.

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.

Different glacier status with atmospheric circulations in Tibetan Plateau and surroundings

Transition-Metal-Catalyzed C−S, C−Se, and C−Te Bond Formation via Cross-Coupling and Atom-Economic Addition Reactions

Chem. Pharm. Bull.(オピニオン)

Methylenebisnicotiflorin: a rare methylene-bridged bisflavonoid glycoside from ripe Pu-er tea

Four new steroidal saponins, named disporosides A-D (1-4), corresponding to (3beta,25R)-3-[(beta-D-glucopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->6)]-beta-D-glucopyrnosyl)oxy]-5beta-spirostan (1), (3beta,25R)-3-[(beta-D-glucopyranosyl-(1-->2)-[6-O-hexadecanoyl-beta-D-glucopyranosyl-(1-->6)]-beta-D-glucopyranosyl)oxy]-5beta-spirostan (2), (3beta,22R,25R)-26-[(beta-D-glucopyranosyl)oxy]-3-[(beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl)-oxy]-5beta -furostan (3), and (3beta,22R,25R)-26-[(beta-D-glucopyranosyl)oxy]-3-[(beta-D-glucopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1 -->6)]-beta-D-glucopyranosyl)oxy]-5beta-furostan (4), have been isolated from the fresh rhizomes of Disporopsis pernyi, together with the three known compounds Ys-I, agavoside B, and (3beta,25R)-3-[(beta-Dxylopyranosyl-(1 -->3)-beta-D-glucopyranosyl-(1- 4)-beta-D-galactopyranosyl)oxy]-5alpha-spirostan-12-one. Their structures were elucidated by spectroscopic analyses, chemical transformations (acid hydrolysis), and comparison with literature data.

Steroidal Saponins from Disporopsis pernyi

Phenolic constituents from the leaves of Syzygium forrestii Merr. and Perry

New cytotoxic lignan glycosides from Phyllanthus glaucus

“Long-Dan” and “Qin-Jiao” are two important TCM herbs since ancient times in China. In the Chinese Pharmacopoeia, the dried roots and rhizomes of four species from the genus Gentiana, e.g. Gentiana manshurica, G. scabra, G. triflora and G. rigescens, are recorded under the name of Gentianae Radix et Rhizoma (“Long-Dan” in Chinese), while the other four species from the same genus including G. macrophylla, G. crassicaulis, G. straminea and G. duhurica are recorded and used as the raw materials of Gentianae Macrophyllae Radix (“Qin-Jiao” in Chinese). On the basis of the establishment of a validated HPLC–UV method for quantifying simultaneously, five iridoid glycosides, e.g. loganic acid (1), swertiamarinin (2), gentiopicroside (3), sweroside (4) and 2′-(o,m-dihydroxybenzyl)sweroside (5) have been used successfully as chemical markers for the comparison of the species used as “Long-Dan”, “Qin-Jiao” and their adulterants in the present study. The results suggested that four iridoid glycosides 1–4 commonly existed in both “Long-Dan” and “Qin-Jiao”, while 2′-(o,m-dihydroxybenzyl)sweroside (5) also existed as one of the major components in “Dian-Long-Dan” species. Moreover, the contents of compounds 1–5 were various in different “Long-Dan” and “Qin-Jiao” species. Herein, we profiled and compared three “Long-Dan” species, four “Qin-Jiao” species and five adulterants by applying multivariate statistical techniques to their HPLC data sets to establish the differences and/or similarities.

Electronic supplementary material
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Min Xu

Papers

Methylenebisnicotiflorin: a rare methylene-bridged bisflavonoid glycoside from ripe Pu-er tea

Steroidal Saponins from Disporopsis pernyi

Phenolic constituents from the leaves of Syzygium forrestii Merr. and Perry

New cytotoxic lignan glycosides from Phyllanthus glaucus

Comparative study on "long-dan", "qin-jiao" and their adulterants by HPLC analysis.