Two new cyclopentenone derivatives and a new cyclooctadienone derivative from Erigeron annuus (L.) PERS., Erigeron philadelphicus L., and Erigeron sumatrensis RETZ

Two new cyclopentenone derivatives, erigerenones A (1) and B (2), and a new cyclooctadienone derivative, erigerenone C (3), were isolated from the aerial parts of Erigeron philadelphicus L. Compound 2 was also isolated from the aerial parts of Erigeron annuus (L.) PERS. and Erigeron sumatrensis RETZ. The structures of 1-3 were elucidated on the basis of their spectral data.     

Ajugareptansin,a new diterpenoid from ajuga reptans (L.)

The structure of a new clerodane diterpene, isolated from $\text{Ajuga}$$\text{reptans}$, has been elucidated by chemical and spectral means and confirmed by X-ray crystallographic studies of the corresponding $\text{p}$-bromobenzoate.     

Isolation and identification of a new neo-clerodane diterpenoid from Teucrium chamaedrys L.

Teucrium chamaedrys L. is an aromatic and medicinal plant used as traditional medicine. Aerial parts of the plant material were dried and extracted with hexane–dichloromethane (extract 1), ethyl acetate–dichloromethane (extract 2) and methanol–dichloromethane (extract 3) in a ratio of 1:1 at rt successively. The solvents were evaporated to give crude extracts. Extract 1 was suspended in water at 60°C then partitioned successively with hexane and ethyl acetate to give hexane and ethyl acetate portions. After the column chromatography (silica gel) of ethyl acetate extract, one new and four known compounds were isolated. The new compound was named as 1(12S,18R)-15,16-epoxy-2β,6β-dihydroxy-neo-cleroda-13(16),14-dien-20,l2-olide-l8,l9-hemiacetal (teuchamaedryn D) (4). The known compounds were teucrin A (1), dihydroteugin (2), teucroxide (3), syspirensin A (5). The chromatographic methods were also applied for extract 3 to isolate verbascoside (6) and teucrioside (7). The structure of isolated compounds was elucidated by spectroscopic methods including LC-TOF/MS, 1D NMR and 2D NMR.     

Two new aromatic compounds from Hericium erinaceum (BULL.: FR.) PERS(1)

Two new aromatic compounds, erinacerins A (1) and B (2), were isolated from the fruiting bodies of Hericium erinaceum (BULL.: FR.) PERS. (Hericiaceae) together with a known compound, hericenone A (3). The structures of the new compounds were elucidated on the basis of their spectral data. It was found that 1 occurred as a racemate.     

Halichonadins K and L, new dimeric sesquiterpenoids from a sponge Halichondria sp

Two new structurally unique dimeric sesquiterpenoids, halichonadins K (1) and L (2), were isolated from an Okinawan marine sponge Halichondria sp. The structures of 1 and 2 were elucidated on the basis of spectroscopic analysis including a single crystal X-ray diffraction analysis and chemical conversion. Halichonadins K (1) and L (2) are homodimers of the eudesmane sesquiterpene linked with a piperidine ring through amide bonds. Halichonadin K (1) showed moderate cytotoxicity against KB cells.     

A new lignan and a new sesquiterpene from Eurotia ceratoides (L.)

A new lignan, rayalinol (1) and a new sesquiterpene kairatene (2) were isolated from Eurotia ceratoides (L.) along with four hitherto unreported syringaresinol, dehydrodiconiferyl aldehyde, dihydrodehydrodiconiferyl alcohol, and dehydrodiconiferyl alcohol and two previously reported constituents ferulic acid and β-sitosterol. The structures of the new constituents were elucidated by extensive spectroscopic means and chemical evidences. Rayalinol is a biogenetically interesting compound with a hitherto unreported 9a homolignane skeleton. Its biosynthetic origin is suggested.     

Five new ent-kaurane diterpenes from Annona squamosa L. pericarps

Abstract

In the present study, five new ent-kaurane diterpenes including 4α-hydroxy-17,19-dinor-ent-kaurane-16-one (1), 4β-hydroxy-16β-H-18-nor-ent-kaurane-17-oic acid (2), 4β,17-dihydroxy-16α-acetoxy-18-nor-ent-kaurane (3), Annosquamosin Z (4) and 16α-H-ent-kaurane-17,18-dioic acid, 17-methy ester (5) were isolated from Annona squamosa L. pericarp. The compounds were also evaluated for their cytotoxic activities against SMMC-7721 and HepG2 cell lines, among which compound 3 exhibited potent cytotoxicity with IC₅₀ value of less than 20?μM.     

Pinusolide, a new diterpenoid from Pinus sibirica and P. korsensis

Conclusions From the neutral fraction of the oleoresin ofPinus sibirica R. Mayr andP. koraensis Sieb. et Zucc. a new diterpenoid has been isolated which we have called pinusolide, whose structure has been shown to be that of methyl labd-8(20)-1,3-dien-16,15-olid-19-oate.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 541–545, September–October, 1970.     

Pinusolide,a new diterpenoid from Pinus sibirica and P. korsensis

Chemistry of Natural Compounds - From the neutral fraction of the oleoresin ofPinus sibirica R. Mayr andP. koraensis Sieb. et Zucc. a new diterpenoid has been isolated which we have called...     

A new ent-norabietant diterpenoid from roots of Euphorbia lathyris L.

A new highly oxidized ent-norabietane diterpenoid named lathyrisol A (1) was isolated from roots of Euphorbia lathyris L. The structure and absolute configuration of 1 were elucidated on the basis of data obtained by HRESIMS, NMR, and the Cu-Kα radiation X-ray diffraction analysis. This compound is the first example of naturally occurring norabietane diterpenoid with an exocyclic olefin at the C-4 position.     

A new ent-clerodane diterpenoid from Crassocephalum bauchiense Huch. (Asteraceae)

A phytochemical investigation of the whole plant of Crassocephalum bauchiense Huch. resulted in the isolation of a new clerodane diterpenoid, ent-2β,18,19-trihydroxycleroda-3,13-dien-16,15-olide (1), together with two known flavonoids 3′,5-dihydroxy-4′,5′,6,7,8-pentamethoxyflavone (2) and 4′,5-dihydroxy-3′,5′,6,7,8-pentamethoxyflavone (3). The compounds were tested against the chloroquine-sensitive 3D7 strain of Plasmodium falciparum. Compound 2 showed weak activity (IC₅₀ = 10.1 g/mL) whilst compounds 1 and 3 were inactive. The structures of the compounds were elucidated by using detailed spectral analyses, especially ¹H and ¹³C NMR, ¹H–¹H COSY, NOESY, HMBC and HR-ESI-MS.     

A new coumarin from Wikstroemia indica （L.） C. A. Mey

A new coumadn was obtained from the stems and roots of Wikstroemia indica (L.) C.A.Mey.Its structure was elucidated as methyl 3-(2-hydroxy-4-(7-hydroxy-6-methoxy-2-oxo-2H-chromen-3-yloxy) phenyl) propanoate by spectroscopic methods.     

A new bisabolane sesquiterpenoid and a new abietane diterpenoid from Cephalotaxus sinensis

Phytochemical investigation of Cephalotaxus sinensis has led to the isolation of a new bisabolane sesquiterpenoid (1), a new abietane diterpenoid (2), and 13 known compounds (3–15). Their structures were elucidated by extensive spectroscopic analysis (MS, UV, IR, and NMR).     

Two new steroidal glucosides from Ophiopogon.japonicus （L.f.） Ker-Gawl

Two new steroidal glucosides, 26-O-β-D-glucopyranosyl （25S）-furost-5-ene-1β,3β,22α,26-tetraol l-O-β-D-xylopyranosyl- （1 → 3）-[α-h-rhamnopyranosyl-（1 → 2）]-[β-D-fueopyranoside and （25R） spirost-5-ene-3β,14α-diol-3-β-O-β-L-rhanmopyranosyl- （1 → 2）-[β-D-xylopyranosyl（1 → 4）]-[-β-D-glucopyranoside, were isolated from the Ophiopogon japonicus （L.f.） Ker-Gaw. Their structures were elucidated by spectroscopic methods.     

Structures of cadinane- and guaiane-type sesquiterpenoids from Enterospermum madagascariensis (Baill.) Homolle

Three new cadinane- and guaiane-type sesquiterpenoids, 2-hydroxy-10-epi-zonarene 1, 2, 15-dihydroxycalamenene 2 and guaia-4, 6-dien-3-one 3, were isolated from the wood of Enterospermum madagascariensis (Rubiaceae) grown in Madagascar. Their structures were established from concerted application of 2D NMR techniques including gs-COSY, gs-HMQC, gs-HMBC and NOESY.     

Briarenol A, a new diterpenoid from a gorgonian '\Briareum sp. (Briareidae)

A new polyoxygenated briarane-type diterpenoid, briarenol A (1), has been isolated from a gorgonian coral belonging to the genus Briareum. The structure, including the relative stereochemistry of briarane 1, was elucidated by the interpretation of spectral data. The configuration of 1 was further supported by molecular mechanics calculations.     

Halichonadins A-D, new sesquiterpenoids from a sponge Halichondria sp.

A new dimeric sesquiterpenoid with two eudesmane skeletons through a urea linkage, halichonadin A (1), as well as three new eudesmane sesquiterpenoids having a carbamate, an isonitrile, or an amino functionality, halichonadins B (2), C (3), and D (4), respectively, have been isolated from a marine sponge Halichondria sp., and the gross structures and relative stereochemistry of 1-4 were elucidated on the basis of spectral data and chemical means.