Teumarin a neo-clerodane diterpenoid from Teucrium marum

A new neo-clerodane diterpenoid, teumarin, was isolated from the aerial part of Teucrium marum. Its structure, 19-acetoxy-4α,18:15,16-diepoxy-2β,6β-dihydroxy-neo-cleroda-13(16),14-dien-20,12S-olide, was established by chemical and spectroscopic means and by comparison with closely related compounds.     

Neo-clerodane diterpenoids from Teucrium pyrenaicum

From the aerial part of Teucrium pyrenaicum three new neo-clerodane diterpenoids have been isolated. Their structures, 3β-acetoxy-4α,18:12S,2OS: 15,16:19, 2OS-tetraepoxy-neo-cleroda-13(16),14-dien-6-one (teupyrenone), 3β,6α,19-triacetoxy- 4α,18:15,16-diepoxy-neo-cleroda-13(16),14-dien-20,12S-olide (teupyreinin), and 3β, 6α,19,2OS-tetra-acetoxy-4α,18:12S,2OS: 15,16-triepoxy-neo-cleroda-13(16), 14-diene (teupyreinidin), were established mainly by spectroscopic means.     

Diterpenoids from Teucrium scorodonia, three neo-clerodane derivatives

From the aerial parts of Teucrium scorodonia the previously known diterpenoid teupolin I and the flavone luteolin have been isolated. In addition, three new neo-clerodane derivatives have also been obtained from the same source. The structures of these new natural diterpenoids have been established by chemical and spectroscopic means and by correlation with known products.     

Neo-clerodane diterpenoids from Teucrium massiliense

From the aerial part of Teucrium massiliense three new neo-clerodane diterpenoids, deacetylajugarin-II, teumassilin and 6,19-diacetylteumassilin, have been isolated, besides the previously known diterpenes montanin C and teucjaponin A. The structures of deacetylajugarin-II (4α,18-epoxy-6α,19-dihydroxy-neo-clerodan-13-en-15,16-olide), teumassilin (4α,18:15,16-diepoxy-6α,12S,19-trihydroxy-neo-cleroda-13(16),14-diene) and 6,19-diacetylteumassilin (6α,19-diacetoxy-4α,18:15,16-diepoxy-12S-hydroxy-neo-cleroda-13(16),14-diene) were established by chemical and spectroscopic means. In addition, the previously known flavones salvigenin and cirsimaritin have also been obtained from the same source.     

Epoxysalviacoccina,neo-clerodane diterpenoid from Salvia plebeia

A new neo-clerodane derivative, epoxysalviacoccin, has been isolated from the aerial part of Salvia plebeia, together with the previously known diterpenoid salviacoccin. The structure of epoxysalviacoccin, 2β,3β; 15,16-diepoxy-10β-hydroxy-neo-cleroda-7,13(16),14-triene-17,12R; 18,19-diolide, has been established by spectroscopic means and by partial synthesis from salviacoccin.     

Dihydroteugin,a neo-clerodane diterpenoid from Teucrium chamaedrys

From the aerial part of Teucrium chamaedrys a new neo-clerodane diterpenoid, dihydroteugin, has been isolated, besides the previously known diterpenoids teucrin A and teugin. The structure of dihydroteugin, (12S)-15,16-epoxy-2β,6β-dihydroxy-neo-cleroda-13(16), 14-diene-18,19:20,12-diolide, was established by chemical and spectroscopic means and by partial synthesis from teugin.     

Neo-clerodane diterpenoids from Teucrium lanigerum

From the aerial part of Teucrium lanigerum, six new neo-clerodane diterpenoids, 7,8-dehydroeriocephalin, teulanigeral, teulanigin, 20-epi-teulanigin, teulanigerin and teulanigeridin, have been isolated. The first of these, 7,8-dehydroeriocephalin, is a natural substance, whereas the other compounds were isolated as their acetyl derivatives after acetylation of an inseparable mixture of natural diterpenoids. The structures of these substances were established mainly by spectroscopic means and, in the case of 7,8-dehydroeriocephalin, by partial synthesis from eriocephalin.     

Neo-clerodane diterpenoids from Ajuga pseudoiva

From the whole plant of Ajuga pseudoiva two epimeric neo-clerodane diterpenoids, 2-acetylivain I and its C-2 epimer 14,15-dihydro-ajugapitin, have been isolated. The structures were established by spectroscopic and chemical means. 2-Acetylivain I had not been previously reported, while its C-2 epimer had been isolated from Ajuga chamaepitys.     

2-keto-19-hydroxyteuscordin,a neo-clerodane diterpene from Teucrium scordium

From the aerial parts of Teucrium scordium a new neo-clerodane diterpenoid, 2-keto-19-hydroxyteuscordin, has been isolated, besides the previously known diterpenoids teucrin E and teucrin H4. The structure of 2-keto-19-hydroxyteuscordin, (12S)-15,16-epoxy-2-keto-19-hydroxy neo-clerodane-13(16),14-dien-18β,6β:20,12-diolide, was established by chemical and spectroscopic means.     

Isoeriocephalin and 20-deacetyleriocephalin,Neoclerodane Diterpenoids from Teucrium lanigerum

From the aerial part of Teucrium lanigerum two new neo-clerodane diterpenoids, 20-deacetyleriocephalin and isoeriocephalin, have been isolated, together with the previously known diterpene eriocephalin. The structures of 20-deacetyleriocephalin [19-acetoxy 4α,18:15,16-diepoxy-7α-hydroxy-6-keto-neo-cleroda-13(16),14-diene-20S,12S-hemiacetal] and isoeriocephalin [19-acetoxy-4α,18:15,16-diepoxy-6α-hydroxy-7-keto-neo-cleroda-13(16),14-diene (20-acetyl)-20S,12S-hemiacetal] were established by chemical and spectroscopic means and by correlation with known compounds.     

Teuchamaedrin C,a neo-clerodane diterpenoid from Teucrium chamaedrys

A new neo-clerodane diterpenoid, teuchamaedrin C, has been isolated from the aerial parts of Teucrium chamaedrys. Its structure, (12S,18S)-15,16-epoxy-neo-clerodane-13(16)14-dien-19,20-olide-18,6β-hemiacetal, was established by spectroscopic and chemical means. In addition, the previously known diterpenoids 6α-hydroxyteuscordin and dihydroteugin were isolated from the same source.     

Neo-clerodane diterpenoids from Teucrium oxylepis subsp. Marianum

Two new neo-clerodane diterpenoids have been isolated from the aerial parts of Teucrium oxylepis subsp. marianum. Their structures, 4,18;15,16-diepoxy-6β,12S-dihydroxy-neo-clerado-13(16),14-dien-20,19-olide (teucroxylepin) and 12S-acetoxy-6β,18; 15,16-diepoxy-4,6-dihydroxy-neo-cleroda-13(16),14-dien-20,19-olide (12-O-acetylteugnaphalodin), were established by chemical and spectroscopic means. In addition, 10 already known neo-clerodane diterpenoids were also isolated from the same source.     

Two new neo-clerodane diterpenoids from Scutellaria barbata

Two new neo-clerodane diterpenoids, 6,7-dibenzoyloxybarbatin C (1, named barbatin D) and 6-(2-acetoxy-3-methylbutanoloxy)-7-(2-carbonyl-3-methylbutanoyloxy) barbatin C (2, named barbatin E) were Isolated from the whole plant of Scutellaria barbata D. Don. Their structures were elucidated by spectroscopic methods including extensive 1D and 2D NMR analyses. In vitro, compounds 1-2 showed cytotoxic activities against three human cancer lines, namely, HONE-4 nasopharyngeal, KB oral epidermoid carcinoma, and HT29 colorectal carcinoma cells, and with ICso values in the range of 3.5-6.7 μM.     

Salviacoccin,a neo-clerodane diterpenoid from Salvia coccinea

A new neo-clerodane diterpenoid, salviacoccin, was isolated from the aerial part of Salvia coccinea. Its structure, 15,16-epoxy-10-hydroxy-neo-cleroda-2,7,13(16), 14-tetraene-17,12R:18,19-diolide, was established by chemical and spectroscopic means and by comparison with closely related compounds.     

Neo-clerodane diterpenoids from Ajuga genevensis

Three new neo-clerodane diterpenoids, ajugavensins A–C, have been isolated from the acetone extract of the aerial parts of Ajuga genevensis and their structures established by spectroscopic means and by comparison with closely related compounds.     

Bitter diterpenoids from Isodon shikokianus var. Intermedius

Four new diterpenoids were isolated from the aerial parts of Isodon shikokianus var. intermedius. The structures of two of them, shikodokaurin A and B, were established.     

Teugin,a neo-clerodane diterpenoid from Teucrium fragile

From the aerial part of Teucrium fragile a new neo-clerodane diterpenoid, teugin, has been isolated. Its structure, 15,16-epoxy- 2β,6β-dihydroxy-neo-cleroda-3,13(16),14-triene-18,19:20,12S-diolide, was established mainly by spectroscopic means.     

Isolation of the diterpenoid teuflin (6-epiteucvin) from Teucrium viscidum var. miquelianum

The diterpenoid teuflin (6-epiteuevin) has been isolated from Teucrium viscidum var. miquelianum. Its base catalysed epimerization into teucvidin was studied under mild conditions and the pathway is discussed.     

Abietane diterpenoids from the root of Salvia phlomoides

From the root of Salvia phlomoides three new abietane diterpenoids, demethylcryptojaponol, 14-deoxycoleon U and salviphlomone, have been isolated, besides the previously known diterpenes 8,13-abietadiene, 8,11,13-abietatriene, royleanone, 7α-acetoxyroyleanone, taxodione, taxodone, cryptojaponol and sugiol. The structures of demethylcryptojaponol (11,12-dihydroxy-8,11,13-abietatrien-7-one), 14-deoxycoleon U (6,11,12-trihydroxy-5,8,11,13-abietatetraen-7-one) and salviphlomone (6α,7β-dihydroxy-8,13-abietadiene-11,12-dione) were established by chemical and spectroscopic means.     

Diterpenoids from Salvia oxyodon and Salvia lavandulifolia

Three new diterpenoids have been detected in Salvia oxyodon and identified as 3β-hydroxy-dehydroabietic acid, 3β-acetoxy-abieta-8(14)-en-18-oic acid 9α,13α-endoperoxide and 3β-hydroxy-abieta-8(14)-en-18-oic acid 9α,13α-endoperoxide. Salvia lavandulifolia yielded two known compounds ursolic acid and galdosol.