0000000000343898
AUTHOR
Orietta Servettaz
Neoclerodane Diterpenoids from Scutellaria pontica
Seven novel neoclerodane diterpenoids, scupontins A-G, have been isolated from the Me2CO extract of the aerial parts of Scutellaria pontica (1-7), together with the known neoclerodanes scutalbin A and scutalpin M. Structures 1-7 were established by exhaustive NMR spectroscopic studies and chemical transformations. Scupontins A-D(1-4, respectively) and scupontins E (5)andF(6) possess unusual [(3¢S,3¢¢S)-3¢-[(3¢¢-acetoxybutyryl)oxy]butyryloxy and [(3¢S,3¢¢S,3¢¢¢S)- 3¢-[[3¢¢-[(3¢¢¢-hydroxybutyryl)oxy]butyryl]oxy]butyryl]oxy substituents, respectively, attached to the C-19 position of the neoclerodane framework. In the case of the 6R,7â-dibenzoate derivative 7 (scupontin G) its absolute config…
Occurrence of (+)-6-desoxyandalusol in Stachys ionica and Stachys distans
Minor diterpenoids from Scutellaria polyodon.
Four minor neoclerodane diterpene constituents were isolated from the aerial parts of Scutellaria polyodon. These compounds were characterized as the new scupolins J (1) and K (2) and the previously known scutalpin O (3) and scutalsin.
Coumarins from Seseli bocconi
Abstract A new khellactone, bocconin, in addition to known compounds, have been isolated from Seseli bocconi subsp. bocconi and subsp. praecox Gamisans . Their structures were elucidated on the basis of spectral analyses and hydrolytic studies.
Neoclerodane Diterpenoids from Scutellaria polyodon
Nine new neoclerodane diterpenoids, scupolins A−I, have been isolated from an Me2CO extract of the aerial parts of Scutellaria polyodon (3−11), together with the known neoclerodanes jodrellin B (1) and scutecolumnin A (2). Structures 3−11 were established by spectroscopic means and by comparison with closely related compounds.
Labdane Diterpenes from Stachys plumosa
Three new labdane diterpenoids were isolated from the aerial parts of Stachys plumosa. The first two (1, 2) were the dextrorotatory enantiomers of the known 6-deoxyandalusol and 13-epijabugodiol. Structures were determined using NMR and MS techniques. The absolute stereochemistry of the third compound (3) was not experimentally proved.
Antifeedant activity of neo-clerodane diterpenoids from Teucrium arduini
Ent-clerodane diterpenoids from six further species of Teucrium
Abstract Fifteen further species of the genus Teucrium have been investigated. Six of them contain known ent -clerodane diterpenoids; the others did not yield any diterpenoid. The chemotaxonomic significance of these results is discussed.
Scuteparvin, a new neoclerodane diterpenoid from Scutellaria parvula
Abstract The diterpenoid fraction occurring in the acetone extract of the aerial parts of Scutellaria parvula has been investigated. Only one neoclerodane diterpenoid, scuteparvin, was isolated and its structure elucidated as 4α,18-epoxy-6α- trans -cinnamoyloxy- neo clerod-13-en-15,16-olide, a new natural product. Scuteparvin is quite similar to the already known ajugarin V from Ajuga remota , the only difference being the occurrence of a trans -cinnamoyl ester system instead of an acetate on the 6α-OH group. This finding confirms that the genera Scutellaria and Ajuga are closely related taxonomically.
Neo-clerodane diterpenoids from Scutellaria lateriflora
Abstract Three new diterpenoids, scutelaterins A-C, have been isolated from Scutellaria lateriflora and their structures established as (11S,13S,16S)-2β,6α,19-triacetoxy-4α,18;11,16;15,16-triepoxy-neo-clerod-14-ene (scutelaterin A), (11S,13S,16S)-6α,19-diacetoxy-2β-(2′-methyl)butyryloxy-4α,18;11,16;15,16-triepoxy-neo-clerod-14-ene (scutelaterin B) and (11S,13S,15R and S)-6α,19-diacetoxy-2β-(2′-methyl)butyryloxy-4α,18;11,16;15,16-triepoxy-neo-clerodan-15-ol (scutelaterin C) by chemical and spectroscopic means. In addition, the already known neo-clerodanes ajugapitin and scutecyprol A were also found in the same source.