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Three new diarylheptanoids and one new monoterpenoid were isolated from the rhizomes of Zingiber officinale together with four known diarylheptanoids, 5-8. Their structures were elucidated mainly by spectroscopic methods, and they were deduced as 5-[4-hydroxy-6-(4-hydroxyphenethyl)tetrahydro-2 H-pyran-2-yl]-3-methoxybenzene-1,2-diol (1), sodium (E)-7-hydroxy-1,7-bis(4-hydroxyphenyl)hept-5-ene-3 S-sulfonate (2), sodium (E)-7-hydroxy-1,7-bis(4-hydroxyphenyl)hept-5-ene-3 R-sulfonate (3), and hydroxycineole-10-O-beta-D-glucopyranoside (4), respectively. Among the isolated compounds, compounds 1, 5, and 8 exhibited strong superoxide anion radical scavenging activities in a phenazine methosulfate-NADH system. In a more biological system, these compounds were demonstrated to exhibit potent protection against lipid peroxidation in mouse liver microsomes exposed to oxidative conditions. These compounds were subsequently tested on primary cultures of rat hepatocytes exposed to oxidative damage, and definitive cytoprotective actions were found.

A phytochemical study on the ethanol extract of the aerial parts of Schnabelia tetradonta led to the isolation of five new compounds, 1-5, together with seven known compounds. The structures of the new compounds were elucidated on the basis of spectral data interpretation as 2alpha,3alpha,23,29-tetrahydroxyolean-12-en-28-oic acid (1), 3-O-beta-d-glucuronopyranosyl-2beta,3beta,16beta-trihydroxy-28-norolean-12-en-15-on-23-oic acid (2), 21-O-beta-d-glucopyranosyl-3beta,21alpha,30-trihydroxyolean-13(18)-en-24-oic acid (3), 6-C-beta-l-arabinopyranosyl-8-C-alpha-l-arabinopyranosylapigenin (4), and 4-acetylaminoethylphenyl 1-O-[6-O-(Z)-p-methoxycinnamoyl-beta-d-glucopyranosyl(1-->2)]-[beta-d-glucopyranosyl(1-->3)]-alpha-l-rhamnopyranoside (5), respectively.

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The introduction of groups with high enthalpies of formation can effectively improve the detonation performance of the compounds. A series of novel energetic compounds (10–13) with high enthalpies of formation, high density, and high nitrogen–oxygen content were designed and synthesized by combining gem-polynitromethyl, 1,2,4-oxadiazole, furoxan, and azo groups. All the new compounds were thoroughly characterized by IR, NMR, elemental analysis, and differential scanning calorimetry. Compounds 10 and 11 were also further characterized with single-crystal X-ray diffraction. Compound 11 has high density (1.93 g cm–3), high enthalpy of formation (993.5 kJ mol–1), high detonation velocity (9411 m s–1), and high heat of detonation (6889 kJ kg–1) and is a potentially excellent secondary explosive.

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The new rearranged‐abietane diterpene 1, the four new triterpenoids 2–5, and the new aminoethylphenyl oligoglycoside 6, besides 19 known compounds, were isolated from the roots of Schnabelia tetradonta, a Chinese endemic herb. The structures of the new compounds were elucidated on the basis of spectroscopic evidence as 12,17‐epoxy‐11,14,16‐trihydroxy‐17(15→16)‐abeo‐abieta‐8,11,13,15‐tetraen‐7‐one (1), 21β‐(β‐D‐glucopyranosyloxy)‐2α,3α‐dihydroxyolean‐12‐en‐28‐oic acid (2), 2β,3β,16β‐trihydroxy‐15‐oxo‐28‐norolean‐12‐en‐23‐oic acid (3), 3β‐[(4‐O‐acetyl‐β‐D‐glucopyranuronosyl)oxy]‐2β,16β‐dihydroxy‐28‐norolean‐15‐oxo‐12‐en‐23‐oic acid (4), 3β‐[(4‐O‐acetyl‐6‐O‐methyl‐β‐D‐glucopyranuronosyl)oxy]‐2β,16β‐dihydroxy‐15‐oxo‐28‐norolean‐12‐en‐23‐oic acid (5), and 4‐[2‐(acetylamino)ethyl]phenyl O‐6‐O‐[(Z)‐p‐methoxycinnamoyl]‐β‐D‐glucopyranosyl‐(1→2)]‐O‐[β‐D‐glucopyranosyl‐(1→3)]‐4‐O‐acetyl‐α‐L‐rhamnopyranoside (6), respectively.

The new rearranged-abietane diterpene 1, the four new triterpenoids 2 ± 5, and the new aminoethylphenyl oligoglycoside 6, besides 19 known compounds, were isolated from the roots of Schnabelia tetradonta, a Chinese endemic herb. The structures of the new compounds were elucidated on the basis of spectroscopic evidence as 12,17-epoxy-11,14,16-trihydroxy-17(15 3 16)-abeo-abieta-8,11,13,15-tetraen-7-one Introduction. ± The genus Schnabelia is distributed exclusively in China, and contains two species of plants, S. oligophylla and S. tetradonta. The latter, S. tetradonta (Sun) C. Y. Wu et C. Chen (Lamiaceae), commonly called −Jin Gu Cao×, is an endemic herbaceous plant used as a febrifuge to relieve internal fevers and as a remedy for rheumatism treatment in traditional Chinese medicine [1]. Up to date, there are few chemical constituents reported from this plant, except for our work dealing with some new compounds including three triterpenoids, an apigenin C-glycoside, an (aminoethyl)phenyl oligoglycoside, and a cyclopeptide from the aerial parts of S. tetradonta