Four New Diterpenoids from Ballota limbata

✍ Scribed by Viqar Uddin Ahmad; Umar Farooq; Ahmed Abbaskhan; Javid Hussain; Muhammad Athar Abbasi; Sarfraz Ahmad Nawaz; M. Iqbal Choudhary

• Publisher: John Wiley and Sons
• Year: 2004
• Tongue: German
• Weight: 112 KB
• Volume: 87
• Category: Article
• ISSN: 0018-019X
• DOI: 10.1002/hlca.200490064

✦ Synopsis

Abstract

Six diterpenoids (1–6) belonging to the clerodane and tetracyclic diterpene types were isolated from the CHCl~3~ extract of Ballota limbata. The structures of the new compounds 1 and 4–6 (named ballatenolide A and limbatenolides A–C, resp.) were established by their spectral data, and their relative configuration was determined by 2D NMR. Compounds 2 and 3 were identified as known clerodanes. Compound 1 had a unique feature, i.e., an α,β‐unsaturated γ‐lactone moiety at C(4)/C(6), whereas limbatenolides A–C (4–6) belonged to the rare class of tetracyclic diterpenoids, which are known to occur only in the genus Ballota. All of the isolated compounds showed inhibitory potential in a cholinesterase‐inhibition assay.