Photosensitized Oxygenation of Abieta-7,9(11)-dien-13β-ol

Dehydration of abiet-8-ene-7β, 13β-diol (ibozol, 1 ) leads to abieta-7,9(11)-dien-13β-ol ( 2 ) which aromatizes slowly to the known abieta-8,11,13-triene ( 3 ). Photosensitized oxygenation of the heteroannular diene 2 yields a mixture from which three compounds were identified; abiet-7-ene-9α, 11α, 13β-triol ( 4 ), abieta-8,11,13-trien-7-one ( 5 ), and abieta-8,11,13-trien-7α-ol ( 6 ).     

Two new pimarane diterpenoids from Strychnos vanprukii Craib

Two new pimarane diterpenoids, 7beta,12beta-dihydroxypimara-8,15-dien-14-one (1) and 14-hydroxy-15,16-dinorpimara-8,11,13-trien-7-one (2), were isolated from the n-hexane extract of the stem of Strychnos vanprukii Craib and their structures were elucidated based on spectroscopic evidences.     

Four new podocarpane-type trinorditerpenes from the bark of Taiwania cryptomerioides

Further studies on the bark of Taiwania cryptomerioides found four new podocarpane derivatives, 1beta,13-dihydroxy-8,11,13-podocarpatriene (1), 14,18-dihydroxy-13-methoxy-8,11,13-podocarpatriene (2), 1beta,14-dihydroxy-13-methoxy-8,11,13-podocarpatriene-2,7-dione (3), and 3beta,14-dihydroxy-13-methoxy-8,11,13-podocarpatrien-7-one (4), together with a known 1beta,13,14-trihydroxy-8,11,13-podocarpatrien-7-one (5). Those structures were elucidated principally from spectral evidence.     

13C NMR Spectra of some diterpenes of Premna latifolia Roxb

¹³C NMR data are presented for premnolal (13-formyl-11,14-dihydroxypodocarpa-8,11,13-triene), the tetraacetate of nellionol (6α,11,14,16-tetra-O-acetylabieta-8,11,13-trien-7-one), 11-ketosandaracopimar-15-en-8β-ol, sandaracopimar-15-en-1β, 8β-diol and its l-keto derivative, and sandaracopimaran-1β,8β,12β-triol, obtained from Premna latifolia Roxb.     

Six podocarpane-type trinorditerpenes from the bark of Taiwania cryptomerioides

Six podocarpane-type trinorditerpenes were isolated from the bark of Taiwania cryptomerioides. Their structures, 14-hydroxy-13-methoxy-8,11,13-podocarpatrien-7-one (1), 13-hydroxy-12-methoxy-8,11,13-podocarpatriene (2), 12-hydroxy-13-methoxy-8,11,13-podocarpatriene (3), 14-hydroxy-13-methoxy-8,11,13-podocarpatriene (4), 13-hydroxy-8,11,13-podocarpatriene (5), and 13,14-dihydroxy-8,11,13-podocarpatrien-7-one (6), were determined principally from spectral evidence.     

Diterpenoids from the Buds of <em>Pinus banksiana</em> Lamb

Three new diterpenoids, namely 7α-hydroxyabieta-8,11,13,15-tetraen-18-oic acid, 7β,15,18-trihydroxyabieta-8,11,13-triene, 13,15-dihydroxypodocarpa-8,11,13-triene, and 12 other known compounds were isolated from buds of Pinus banksiana Lamb. All these compounds, except for 7-oxodehydroabietinol, were isolated for the first time from this plant. Their structures were elucidated by detailed spectroscopic studies and comparison with published data. All isolated compounds were tested for cytotoxic and antibacterial activities. Overall, two compounds, 7-oxodehydroabietinol and 18-nor-4,15-dihydroxyabieta-8,11,13-trien-7-one, showed moderate cytotoxicity against a human lung carcinoma cell line.     

Seco-Abietanoids from Cryptomeria japonica and Their Inhibitory Activity Toward Xanthine Oxidase

Chemistry of Natural Compounds - A new seco-abietanoid, 12-methoxy-7-oxo-6,7-secoabieta-8,11,13-trien-6-oic acid (1), and a known seco-abietanoid,12-hydroxy-6,7-secoabieta-8,11,13-triene-6,7-dial...     

穿心莲内酯硫酸酯化反应体系中四个新的衍生物的分离与表征

通过色谱方法, 从复杂的穿心莲内酯硫酸酯化反应体系中分离获得4个新的穿心莲内酯衍生物, 应用谱学方法进行了表征. 主要利用1H NMR, 13C NMR, DEPT, 1H-1H COSY, HSQC, HMBC及NOSEY等1D和2D NMR技术, 并通过与母体化合物NMR数据的对比分析, 鉴定这4个化合物分别为3,19-二羟基-8,11,13-赖百当三烯-15,16-内酯(1), 3-羟基-8,11,13-赖百当三烯-15,16-内酯-19-硫酸酯(2), 8,11,13-赖百当三烯-15,16-内酯-3,19-二硫酸酯(3), 3-羟基- 8(R)-12(S)-8(12)-环氧-13-赖百当烯-15,16-内酯-19-硫酸酯(4).     

Inuroyleanol and 7-ketoroyleanone,two novel diterpenoids of Inula royleana DC

From the roots of Inula royleana DC (Compositae), two novel tricyclic diterpenoids, named inuroyleanol and 7-ketoroyleanone, have been isolated and their structures established. Inuroyleanol is 11,14-dihydroxy-12-methoxy-abieta-8,11,13-trien-7-one (3a) and 7-ketoroyleanone is 12-hydroxy-abieta-8,12-dien-7,11,14-trione (1d). Inuroyleanol provides a link in the series of naturally occurring oxidative metabolites of the ferruginol (2) skeleton.     

Synthesis of 12-deoxyroyleanone, cryptoquinone, 11,14-dihydroxy-8,11,13-abietatrien-7-one, and related derivatives from dehydroabietic acid

Naturally occurring abietane quinones and hydroquinone, namely, 12-deoxyroyleanone (1a), cryptoquinone (4a), and 11,14-dihydroxyabieta-8,11,13-trien-7-one (5a), together with the epimers of tryptoquinones D (2) and F (3), were first synthesized from dehydroabietic acid (6).     

Chiral Synthesis of 13-Acetyl-12-hydroxy-podocarpane-8, 11,13-triene-7-one

Most diterpenoids exhibit significant bioactivities, such as: antibacterial1,2, antider- matophytic2,3, antioxidant4, etc. 13-Acetyl-12-hydroxy-podocarpane-8,11,13-triene-7-one is a diterpene which has been synthesized by Sukumer et al. from the racemic trans isomer 45. Scheme 1Reagents and conditions: i) n-BuLi, n-hexane , r.t., 4 h (70%); ii) 5% Pd/C, ethanol (95%); iii) BF3.Et2O, CH2Cl2, r.t., 12 h (93%); iv) acetyl chloride, anhydrous AlCl3, -5(C, 4 h (90%); v) CrO3/ HOAc/H2O, r.…     

18-Succinyloxyabieta-8,11,13-triene as a new component from green shoots of the Siberian fir

A new diterpene derivative, 18-succinyloxyabieta-8,11,13-triene, was isolated from the acidic fraction of the extract from wood greens of a Siberian fir. The chemical structure of the molecule was established on the basis of spectroscopy and confirmed by partial synthesis from abieta-8,11,13-trien-18-ol. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1697–1698, July, 2005.     

Bioactive diterpenes from Clerodendrum kaichianum

Bioassay-guided isolation studies of the extract of Clerodendrum kaichianum Hsu., a new rearranged abietane diterpene and five known diterpene compounds were isolated by various chromatography methods. Their structures were identified by means of spectroscopic methods, including 1D- and 2D-NMR spectroscopy, as (16R)-12,16-epoxy-11,14,17-trihydroxy-17(15-->16)-abeo-8,11,13-abietatrien-7-one (1), villosin A (2), salvinolone (3), 14-deoxyloleon U (4), 5,6-dehydrosugiol (5), and coleon U (6). Compounds 1, 2, 3, and 5 are reported for the first time for this genus. Compounds 1, 2, and 6 demonstrated potent cytotoxic activities against the HL-60 tumor cell line.     

Evaluation of the antiviral and antimicrobial activities of triterpenes isolated from Euphorbia segetalis

A phytochemical reinvestigation of the whole plant of Euphorbia segetalis yielded five tetracyclic triterpenes: 3beta-hydroxy-cycloart-25-en-24-one (1), cycloart-25-ene-3beta,24-diol (2), cycloart-23-ene-3beta,25-diol (3), lanosta-7,9(11),24-trien-3beta-ol (4) and lanosta-7,9(11),24(31)-trien-3beta-ol (5). beta-acetoxy-cycloart-25-en-24-one (1a) and glutinol (6), lupenone (7), dammaranodienol (9), cycloartenol acetate (10), 24-methylenecycloartanol acetate (11) and beta-sitosterol (12), isolated previously, were evaluated for their antiviral activities against Herpes simplex virus (HSV) and African swine fever virus (ASFV). Lupenone exhibited strong viral plaque inhibitory effect against HSV-1 and HSV-2. The in vitro antifungal and antibacterial activities of la, cycloart-23-ene-3beta,25-diol, 3-acetate (3a) and 6-12 were also investigated.     

A new pyrrolidine derivative and steroids from an algicolous Gibberella zeae strain

A new pyrrolidine derivative, 3-hydroxy-5-(hydroxymethyl)-4-(4'-hydroxyphenoxy)pyrrolidin-2-one (1), and eight known steroids, (22E,24R)-7beta,8beta-epoxy-3beta,5alpha,9alpha-trihydroxyergosta-22-en-6-one (2, a reassigned structure of (22E,24R)-5alpha,6alpha-epoxy-3beta,8beta,14alpha-trihydroxyergosta-22-en-7-one), (22E,24R)-3beta,5alpha,9alpha-trihydroxyergosta-7,22-dien-6-one (3), (22E,24R)-3beta,5alpha-dihydroxyergosta-7,22-dien-6-one (4), (22E,24R)-ergosta-7,22-dien-3beta/,5alpha,6beta-triol (5), (22E,24R)-ergosta-5,22-dien-3beta-ol (6), (22E,24R)-5alpha,8alpha-epidioxyergosta-6,22-dien-3beta-ol (7), (22E,24R)-5alpha,8alpha-epidioxyergosta-6,9(11),22-trien-3beta-ol (8), and (22E,24R)-1(10 --> 6)-abeo-ergosta-5,7,9,22-tetraen-3alpha-ol (9), were isolated from the cultures of Gibberella zeae, an endophytic fungus isolated from the marine green alga Codium fragile. Their structures and relative stereochemistry were elucidated by 1D, 2D NMR and mass spectroscopic techniques. Compound 1 showed cytotoxicity against A-549 and BEL-7402 cell lines.     

Asporyergosterol, a new steroid from an algicolous isolate of Aspergillus oryzae

Asporyergosterol (1), a new steroid with an E double bond between C-17 and C-20, was identified from the culture extracts of Aspergillus oryzae, an endophytic fungus isolated from the marine red alga Heterosiphonia japonica. Moreover, four known steroids including (22E,24R)-ergosta-4,6,8(14),22-tetraen-3-one (2), (22E,24R)-3beta-hydroxyergosta-5,8,22-trien-7-one (3), (22E,24R)-ergosta-7,22-dien-3beta,5alpha,6beta-triol (4), and (22E,24R)-5alpha,8alpha-epidioxyergosta-6,22-dien-3beta-ol (5) were isolated. Structures of these compounds were unambiguously established by spectroscopic techniques and by comparison with literature values. All the isolates exhibited low activity to modulate acetylcholinesterase (AChE).     

Agnatasterone A and B,Unusual Pregnane Steroids Isolated from the North-East Atlantic Sponge Axinella agnata

Two novel pregnatrienolones isolated in very small amounts from the North-East-Atlantic demosponge Axinella agnata (Tetractinomorpha, Axinellida) are unique in having C(2)?C(3) (or C(3)?C(4)), C(7)?C(8), and C(16)?C(17) bonds and a 12β-OH group which, being strongly H-bonded to a 20-keto group, resists acylation. ¹H- and ¹³C-NMR spectroscopy of the steroids and of products of their selective epoxidation or reduction allow us to propose the structures (+)-12β-hydroxy-5α-pregna-2,7,16-trien-20-one ( = agnatasterone A, (+)- 1 ), and (+)-12β-hydroxy-5α-pregna-3,7,16-trien-20-one ( = agnatasterone B. (+)- 5 ), for the two steroids with minimal recourse to model compounds.     

ENANTIOSELECTIVE TOTAL SYNTHESES OF 13-ACETYL- 12-HYDROXY-PODOCARPANE- 8,11,13-TRIENE-7-ONE

ABSTRACT

A enantioselective total synthetic route to (+)-13-acteyl-12-hydroxy-podocarpane-8,11,13-triene-7-one 1a and (?)-13-acetyl-12-hydroxy-podocarpane-8,11,13-triene-7-one 1b from (S)-(?)-α-cyclocitral 8a and (R)-(+)-α-cyclocitral 8b was developed.     

Complete assignments of 1H and 13C NMR spectral data for a novel diterpenoid from Semiaquilegia adoxoides

Semiaquilegoside A (1), a new diterpenoid, was isolated from the roots of Semiaquilegia adoxoides. Its chemical structure was established as 3beta, 11- dihydroxy-12-O-beta-D-glucopyranosyl-8,11,13-abietatrien-6-one through spectroscopic techniques and chemical analysis.     

Three New Abietane‐type Diterpenes from the Bark of Cryptomeria japonica

Three new abietane‐type diterpenoids, 7β‐acetoxy‐12‐methoxyabieta‐8,11,13‐triene‐6α,11‐diol ( 1 ), 7α‐acetoxy‐12‐methoxyabieta‐8,11,13‐triene‐6α,11‐diol ( 2 ), and 6α‐acetoxy‐12‐methoxyabieta‐8,11,13‐triene‐7α,11‐diol ( 3 ), as well as two known abietane‐type diterpenoids, 12‐methoxyabieta‐8,11,13‐triene‐6α,7β,11‐triol ( 4 ) and 6α‐acetoxy‐12‐methoxyabieta‐8,11,13‐triene‐7β,11‐diol ( 5 ), were isolated from the MeOH extract of the bark of Cryptomeria japonica. Their structures were determined by analysis of spectroscopic data and comparison of NMR data with those of related metabolites.