[Advances in studies on structure and pharmacological activities of natural tirucallane-type triterpenoids].

The tirucallane-type triterpenoids, composed of six isoprene units, belong to a group of tetracyclic triterpenoids. Although the naturally-derived tirucallane-type triterpenoids were found in a small amount, the kind of compounds showed various structures, which consist of apo-type, linear said-chain-type and cyclolike said-chain-type and broad bioactivities, such as cytotoxicity, anti-inflammation, antioxidation and anti-plasmin, etc. This paper summarized origins, structures and bioactivities of tirucallane-type triterpenoids in recent ten years. The future research and exploration of tirucallane-type triterpenoids were discussed and prospected.

[Reviews on natural monocyclic sesquiterpenoids and their bioactivities].

Sesquiterpenes are a class of terpenoids composed of three isoprene units( 15 carbons). Sesquiterpenoids possess a variety of different structures,including acyclic sesquiterpenes,monocyclic sesquiterpenoids,bicyclic sesquiterpenoids,tricyclic sesquiterpenoids,tetracyclic sesquiterpenoids and macrocyclic sesquiterpenoids. Among them,a large number of monocyclic sesquiterpenoids were isolated and display extensive bioactivities,such as cytotoxic,antioxidant,anti-inflammatory,antibacterial and other activities. In this review,we summarized the progress about the phytochemistry and biological activities of monocyclic sesquiterpenoids( a total of161 compounds) reported from 2014 to 2018( 5 years),including megastigmanes,monocyclofarnesol-type,bisabolane-type,germacrane-type,and other types of monocyclic sesquiterpenoids. Furthermore,several future research perspectives and development of sesquiterpenoids as potential therapeutic agents were discussed as well.

[Reviews on natural naphthoquinones and their bioactivities].

The naphthaquinones are widely distributed in plants. They are usually in higher plants, but a few of them were also found in microorganisms. There is a lot of research showing that they had multiple pharmaco-activities such as cytotoxic, antioxidant, anti-inflammatory and antibacterial activities, etc. In recent years, they have attracted extensive attention at home and abroad especially in terms of the anti-tumor activity. For further research, 69 new natural naphthoquinones reported in the last five years (2013-2017) were reviewed. They were divided into five major types: simple 1,4-naphthoquinones, furan and pyran naphthoquinones, 1,2-naphthoquinones, naphthohydroquinones and naphthoquinone polymers, which showed cytotoxic, antioxidative, anti-inflammatory and antibacterial biological activities, et al. The research of these compounds in the future was also proposed.

[Constituents isolated from n-butanol extract of leaves of Moringa oleifera].

Seventeen compounds were isolated from n-butanol extract of the leaves of Moringa oleifera, using column chromatography over macroporous resin HP-20,Sephadex LH-20, and ODS. Their structures were identified as two carboline,tangutorid E(1) and tangutorid F(2); three phenolic glycosides,niazirin(3)，benzaldehyde 4-O-α-L-rhamnopyranoside(4) and 4-O-ß-D-glucopyranosidebenzoic acid(5); four chlorogenic acid and derivatives,4-caffeoylquinic acid(6),methyl 4-caffeoylquinate(7),caffeoylquinic acid(8) and methyl caffeoylquinate(9); two nucleosids,uridine(10) and adenosine(11); one flavone,quercetin 3-O-ß-D-glucopyranoside(12); five other types of compounds,phthalimidineacetic acid(13),3-pyridinecarboxamide(14),3,4-dihydroxy-benzoic acid(15),5-hydroxymethyl-2-furancarboxylic acid(16) and 5-hydroxymethyl-2-furaldehyde(17) by the spectral data of ¹H, ¹³C-NMR and MS. Among them,compounds 1-2,7,9-10,16 and 17 were isolated from M. oleifera for the first time.