Structure and Absolute Configuration of Abietane Diterpenoids from Salvia clinopodioides: Antioxidant, Antiprotozoal, and Antipropulsive Activities

Abstract

The aerial parts of Salvia clinopodioides afforded abietanes 1a, 2a, and 3 (clinopodiolides A−C), two of which possess an unusual lactol moiety at C-19−C-20, together with an icetexane named clinopodiolide D (4a). Their structures were established by spectroscopic means, mainly 1 H and 13 C NMR, including 1D and 2D homo-and heteronuclear experiments. The antioxidant, antiprotozoal, and antidiarrheal effects of the isolates were evaluated. Compounds 2a and 3 showed better effects than α-tocopherol in the inhibition of lipid peroxidation with IC 50 (μM) = 5.9 ± 0.1 and 2.7 ± 0.2, respectively, and moderate activity in the DPPH assay. All tested compounds showed moderate antiamoebic and antigiardial activity, as well as a good antipropulsive effect.

Alpha-Glucosidase and Alpha-Amylase Inhibitory Activities of Novel Abietane Diterpenes from Salvia africana-lutea

“…In particular, the HMBC showed a correlation between a proton at 5.6 (H-19) and the C-20 (180.1)/C-4 (37.0)/C-5 (50.2). Other 2D spectra in comparison with literature data confirmed the structure of compound 5 as clinopodiolide A [33]. On the other hand, compound 6 showed typical NMR signals similar to the ones of compound 5 (Table 1 and Table 2), except for the presence of an extra methoxyl signal, which was placed on C-12 from the HMBC correlations.…”

“…On the other hand, compound 6 showed typical NMR signals similar to the ones of compound 5 (Table 1 and Table 2), except for the presence of an extra methoxyl signal, which was placed on C-12 from the HMBC correlations. Other 2D spectra in comparison with literature data confirmed the structure of compound 6 as clinopodiolide B [33]. The occurrence of the lactol moiety at C-19–C-20 is very unusual in nature and it has been recently isolated for the first time from Salvia clinopodioide .…”

Vibrational Circular Dichroism Absolute Configuration of Natural Products From 2015 to 2019

“…Considering that natural occurring 115, 117, and 118 share a common biosynthetic origin with 113, it could be assumed they have the same AC. 66 Three biogenetically interesting entkauranes (−)-alboatisins 119-121 ( Figure 30), isolated from the aerial parts of Isodon albopilosus, have been studied calculating OR values, IR, VCD, ECD, UV-Vis, and molecular orbital energies by DFT. The studies provided a detailed structural characterization and the AC followed from the VCD and ECD results.…”

Structural Elucidation of Malonylcommunol and 6β-Hydroxy-trans-communic Acid, Two Undescribed Diterpenes from Salvia cinnabarina. First Examples of Labdane Diterpenoids from a Mexican Salvia Species

“…Continuing with our systematic study of the genus Salvia in Mexico, and ongoing investigation for biological activity diterpenes of chemosystematic importance [15], we report herein the first study on a wild population of S. cinnabarina collected in the State of Puebla (Mexico). Several diterpenoids of the labdane (1-4) and isopimarane (5)(6) skeletons were isolated, as well as two eudesmane-type sesquiterpenoids (7)(8), phtalic acid (9), tyrosol derivatives (10) and the flavone salvigenin (11).…”