neo-Clerodane Diterpenes from Salvia herbacea

Abstract

Chemical investigation of the aerial parts of Salvia herbacea led to the isolation of eight new neo-clerodane diterpenes (1-8), named tehuanins A-H, and three known compounds. The structures of these compounds were determined by analysis of their spectroscopic data. Three of the new diterpenes possess a 1,8-epoxy group (1-3). This unusual structural feature was confirmed by X-ray diffraction of 1. The structure of the previously isolated 1α,10α-epoxysalviarin was revised. The absolute configuration of 6 was established by X-ray diffraction analysis of its bromo derivative 6a. Cytotoxic and anti-inflammatory activities of these diterpenes were examined. None of the compounds were considered to be cytotoxic; however, compound 7 exhibited anti-inflammatory activity comparable to that of indomethacin.

Clerodane diterpenes: sources, structures, and biological activities

“…The 1β,10β-epoxy group of 627–630 from Salvia herbacea was deduced by analysis of spectroscopic data. 249 Tehuanin G ( 630 ) exhibited anti-inflammatory activity (IC 50 0.24 μM/ear) comparable to that of indomethacin, the reference compound. 249 In contrast, the C-1(2)-epoxy group of 632–634 from S. reptans has an α-orientation.…”

“…249 Tehuanin G ( 630 ) exhibited anti-inflammatory activity (IC 50 0.24 μM/ear) comparable to that of indomethacin, the reference compound. 249 In contrast, the C-1(2)-epoxy group of 632–634 from S. reptans has an α-orientation. 252,253 Except for the stereochemistry of the C-18–C-19 lactone ring fusion ( trans in 632 , cis in 633), compounds 632 and 633 have identical structures with both A/B and B/C cis ring fusions, as established by X-ray analysis.…”

“…252,253 Furthermore, tehuanins A–C ( 635–637 ) from S. herbacea contain a 1,8-oxygen bridge; this unusual structural feature was confirmed by X-ray diffraction of 635 . 249 …”

Bioactive phytochemicals from shoots and roots of Salvia species

“…In a study performed on S. herbacea, 8 new neoclerodane diterpenes, named tehuanins A-H (121-128), were isolated from the aerial parts, however, none of these chemicals had cytotoxic effect against cancer cells (Bautista et al 2012). Similarly, three new clerodane diterpenoids, splendidins A-C (129, 131, 132) isolated from S. splendens (splendidin C being the first diterpenoids glucoside isolated from this plant) did not show any effect against cancer cells (Pan et al 2011).…”

Teotihuacanin, a Diterpene with an Unusual Spiro-10/6 System from Salvia amarissima with Potent Modulatory Activity of Multidrug Resistance in Cancer Cells

“…14 The pharmacological properties of compounds isolated from this species have not been described to date. In our continuing efforts in the search for new bioactive natural products from the genus Salvia, 9,15 a reinvestigation of the chemical composition of S. amarissima was undertaken. Aerial portions of this plant were collected in 2014 from the mountains surrounding the Teotihuacan Valley.…”