1. Department of Chemistry and Chemistry of Natural Product; Faculty of Pharmacy; University of Science and Technology; Sana'a Yemen
2. Department of Chemistry; University of Alabama in Huntsville; Huntsville AL 35899 USA
3. Programa de Pós-Graduação em Biotecnologia; Universidade Federal do Pará; Belém PA 66075-900 Brazil
4. Pharmacognosy Department; Faculty of Clinical Pharmacy; Albaha University; Al Baha Saudi Arabia
5. Department of Pharmacognosy and Phytochemistry; Faculty of Pharmacy; Sana'a University; Sana'a Yemen
6. Department of Chemistry; Faculty of Science; Albaha University; Al Baha Saudi Arabia