Cytotoxic constituent of Melicope latifolia (DC.) T. G. Hartley

• Main Authors: Lim, Pei Cee, Ali, Zulfiqar, Khan, Ikhlas A., Khan, Shabana, Kassim, Nur Kartinee, Awang, Khalijah, Shaari, Khozirah, Ismail, Amin
• Format: Article
• Published: Taylor & Francis 2022
• Subjects: QD Chemistry; RM Therapeutics. Pharmacology
• Online Access: http://eprints.um.edu.my/33844/

An undescribed conjugated sesquiterpene, amelicarin (1), together with nine known compounds (2-10) were isolated for the first time from Melicope latifolia. Their structures were elucidated by extensive NMR spectroscopic and mass spectrometric methods. The conjugated sesquiterpene possesses a unique 6/6/9/4-ring fused tetracyclic skeleton. The proposed biosynthesis pathway of 1 consist of three reactions steps: (1) polyketide formation, (2) cyclisation and (3) addition to form the conjugated sesquiterpenoid as final metabolite. Out of the ten isolated metabolites, amelicarin (1) showed activity against 4 cancerous cell lines namely SK-MEL skin cancer, KB oral cancer, BT-549 breast cancer, and SK-OV-3 ovarian cancer with IC50 values between 15 and 25 mu g/mL.