Chemical constituents from the aerial parts of Musella lasiocarpa

Phytochemical investigation of the aerial parts of the monotypic plant,Musella lasiocarpa,led to the isolation of four rare bicyclic diarylheptanoids,musellarins B-E(2-5),two new phenylphenalenones,2-methoxy-9-(3′,4′-dihydroxyphenyl)-1H-phenalen-1-one(9),2-methoxy-9-(3′-methoxy-4′-hydroxyphenyl)-1H-phenalen-1-one(10),a new acenaphtylene derivative,trans-(1S,2S)-3-(4′-methoxyphenyl)-acenaphthene-1,2-diol(13),and two new sucrose esters,1,2′,3′,4′,6′-O-pentaacetyl-3-O-trans-p-coumaroylsucrose(16),1,2′,3′,4′,6′-O-pentaacetyl-3-O-cis-p-coumaroylsucrose(17),together with nine known compounds.In addition,(4E,6E)-1-(3′,4′-dihydroxyphenyl)-7-(4′′-hydroxyphenyl)-hepta-4,6-dien-3-one(15)was isolated for the first time from a natural source.The structures of new compounds were elucidated by analysis of their spectroscopic data.Compounds 2,6,8-10,12,and 14 were cytotoxic toward several of the human tumor cell lines(HL-60,SMMC-7721,A-549,MCF-7,and SW480).Of these,the new compound 9 was the most potent one,with IC50 values of 5.8,10.3,6.3,3.3,and 2.3μM,respectively.

The Role of Endolymphatic Hydrops in Patients with Pantonal Idiopathic Sudden Sensorineural Hearing Loss:A Cause or Secondary Reaction

The purpose of this study was to investigate the presence of endolymphatic hydrops(EH)in both affected and unaffected ears of patients with pantonal unilateral idiopathic sudden sensorineural hearing loss(ISSNHL)using three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging(3D-FLAIR MRI)and further evaluate the significance of EH in this disorder.Twenty-seven ISSHL patients were enrolled in this study.3D-FLAIR MRI was performed 24 h after intratympanic injection of gadolinium-diethylenetriaminepentaacetic acid(Gd-DPTA).The incidences of EH in the affected ears and contralateral unaffected ears were compared and the correlations of EH with vertigo or prognosis were analyzed using the Chi-square test.The results showed that the incidence of EH was 68.0%(17/25)in the affected ears and 34.8%(8/23)in the unaffected ears.There was a statistically significant difference between affected ears and unaffected ears in regard to the incidence of EH(P<0.05).There were no significant correlations of EH with vertigo(P=1.000)or with prognosis(P=0.359)in the affected ears.In conclusion,there is EH in the inner ear of patients with pantonal ISSNHL;EH is not related to vertigo,a concomitant symptom of ISSNHL,and the prognosis of this condition.The presence of EH may be a secondary reaction following the impairment of the inner ears with pantonal ISSNHL.

Lycopodine-Type Alkaloids from Lycopodium japonicum

Three new lycopodine-type alkaloids,4a-hydroxyanhydrolycodoline(1),4a,6a-dihydroxyanhydrolycodoline(2),and 6-epi-8b-acetoxylycoclavine(3),and an artifact,lycoposerramine G nitrate(4),along with seventeen related known compounds,were isolated from the club moss Lycopodium japonicum Thunb.ex Murray(Lycopodiaceae).Their structures were elucidated by extensive spectroscopic methods as well as X-ray analysis.Compounds 1–4 were evaluated for their acetylcholine esterase inhibitory activity.

Lycodine-Type Lycopodium Alkaloids from the Whole Plants of Huperzia serrata

t Three new lycodine-type Lycopodium alkaloids,namely 1-methyllycodine(1),8a-hydroxy-15,16-dehydro-desN-methyl-a-obscurine(2),N-methyl-16-hydroxyhuperzine B(3),and one new natural lycodine-type Lycopodium alkaloid,N-methylhuperzine A(4),along with 11 known analogues(5–15),were isolated from the whole plants of club moss Huperzia serrata.The structures of 1–4 were elucidated on the basis of NMR spectroscopic and mass spectrometry data.Among them,compound 1 was the first lycodine-type alkaloid possessing a methyl group at C-1.In addition,the structure of 5 was confirmed by the single-crystal X-ray crystallography data and its^(13)C NMR was reported for the first time in current study.Compounds 1–5 were tested their BACE1 inhibitory activity.

(±)-Evodiakine,A Pair of Rearranged Rutaecarpine-Type Alkaloids From Evodia rutaecarpa

(±)-Evodiakine(1a and 1b),a pair of rearranged rutaecarpine-type alkaloids with an unprecedented 6/5/5/7/6 ring system,were isolated from the nearly ripe fruits of Evodia rutaecarpa.Separation of the enantiomers have been achieved by chiral HPLC column.The structures of(±)-evodiakine were unambiguously elucidated by 1D and 2D NMR spectra,mass spectrometry,and single-crystal X-ray diffraction.Their absolute configurations were determined by comparison of experimental and calculated electronic circular dichroism spectra.A hypothetical biogenetic pathway for(±)-evodiakine was also proposed.Compounds 1a,1b,and the racemate(1)were tested for their cytotoxic and anti-inflammatory activities.

Carinatines A and B,Lycopodium Alkaloids from Phlegmariurus carinatus

Carinatine A(1),a C16N2-type Lycopodium alkaloid possessing a 5/6/6/6 ring system formed by a new C-4/C-12 bond,and carinatine B(2),the first derivative of lycojaponicumin C,along 16 known compounds,were isolated from the whole plant of Phlegmariurus carinatus.Their structures were elucidated based on the spectroscopic data.The two new isolates were no inhibitory activity for the acetylcholinesterase(AChE).

New Lycopodium alkaloids from Lycopodium obscurum

Three new Lycopodium alkaloids,obscurumines C-E(1-3),along with nine known compounds,were isolated from the club moss Lycopodium obscurum L.Structures of the new compounds were determined on the basis of their spectroscopic analysis and the relative configurations of 1 were established by X-ray crystallographic analysis.All the new isolates were tested for the acetylcholinesterase(AChE)inhibitory activity.

Exploring of drug leads from diversity-oriented Michael-acceptor library derived from natural products

A potential strategy for drug lead identification and in-active natural products re-discovery is elaborated.Starting from fifteen structurally diverse natural products,a focused library featured by Michael acceptors is constructed with IBX mediated oxidation.Biological assay on five tumor cell lines indicates that four Michael acceptors,8a,11a,12a,14a,are with improved cytotoxicity(3-10 folds more potent than the parent compounds),which merit further investigations.Further thiol-sensitive assay of the active hit 8a revealed that it was an irreversible Michael acceptor.The results suggest that the strategy is not only effective and relatively high discovery rate(28%),but also resource saving.

Euglobal-IIIa, a novel acylphloroglucinol-sesquiterpene derivative from Eucalyptus robusta: absolute structure and cytotoxicity

Euglobal-IIIa (1), a novel acylphloroglucinol-sesquiterpene derivative, and a known analogue, have been isolated from leaves of Eucalyptus robusta. The structures was elucidated by extensive spectroscopic data and by comparison with data reported in literature, while the absolute configuration of 1 was determined by the X-ray diffraction analysis. Compound 1 exhibited comparable cytotoxicity with that of cisplatin against five human cancer cell lines HL-60, SMMC-7721, A-549, MCF-7, and SW480 with IC50 values of 15.7, 15.5, 17.6, 14.3, and 21.8 μM, respectively.

Lyconadins G and H,Two Rare Lyconadin-Type Lycopodium Alkaloids from Lycopodium complanatum

Two rare lyconadin-type Lycopodium alkaloids,lyconadins G(1)and H(2),together with four known ones(3–6),were isolated from Lycopodium complanatum.The structures were determined on the basis of their spectroscopic analyses,and the absolute configuration of 1 was established by an X-ray crystallographic analysis.It is the first time to establish the absolute configuration of lyconadin-type Lycopodium alkaloid by an X-ray diffraction experiment.In addition,these findings may provide more information for the biosynthesis of lyconadins.

Four new labdane-type diterpenoid glycosides from Diplopterygium laevissimum

Four new labdane-type diterpenoid glycosides,laevissiosides A-D(1-4)were isolated from the 95%ethanol extract of Diplopterygium laevissimum(Christ)Nakai,along with two known analogues,18-b-D-glucopyranosyl ester-sclareol(5)and 18-hydroxy-sclareol(6).The structures of compounds 1-4 were elucidated by extensive 1D and 2D NMR spectroscopy as well as high-resolution MS analyses.All isolated compounds were evaluated for their cytotoxic effects.

Synthesis of L-Ascorbic Acid Lactone Derivatives

A small focused library which comprised of L-AA lactone derivatives was built with a facile method.This reported method was optimized by modifying the acidity of the solvent.As a result,12 L-AA lactones were synthesized.Among these lactones,lactones 8–12 were new compounds.The cytotoxicity of these synthetic compounds were investigated.

Discovery and Asymmetric Total Synthesis of Phlegmine A as a Selective Inhibitor of ASIC1a

Phlegmine A(1),a novel type of Lycopodium alkaloid with a unique skeleton,was isolated from the rare and endangered herbal medicinal plant,Phlegmariurus phlegmaria.Spectroscopic methods and X-ray diffraction analysis were employed to unambiguously elucidate the structure of phlegmine A(1).Furthermore,we realized the asymmetric total synthesis of the natural product phlegmine A(1)in 18 linear steps from commercial ingredients,achieving a 1.3%overall yield.An intramolecular carbene cyclization,dimethyldioxirane(DMDO)enamine oxidation,and Stevens rearrangement were exploited to establish the sterically congested vicinal quaternary centers,and an epimerization/aldol condensation/deacetylation reaction was utilized for the rapid assembly of enone at the final step.During our semisynthesis attempts,a novel transformation was developed to constructα-aminoketone from enamine N-oxide.Moreover,the synthetic sample obtained from this work enabled the successful verification of phlegmine A(1)as a new type of highly selective acidsensing ion channel 1a(ASIC1a)inhibitor,which also exerted an in vivo analgesic effect,rendering it a promising lead compound.