Seven undescribed pyrrole-2-carbaldehydes (pyrrolemorines A-G), along with four known analogs, were isolated from the aqueous extract of Moringa oleifera seeds. The structures were elucidated by comprehensive spectroscopic and chemical analyses using HRMS and NMR spectra, acid hydrolysis, and Rh2(OCOCF3)4-induced ECD experiments. Pyrrolemorines A, E, and pyrrolemarumine displayed neuroprotective activities against oxygen-glucose deprivation/reperfusion injury in PC12 cells by regulating NF-κb and Nrf2.

The natural limonoids distributed mainly in the Meliaceae and Rutaceae plants are known for their unique and complex structure with high degree oxidation and cyclic rearrangement. However, these compounds exhibit a broad range of biological activities such as insecticidal, antibacterial, antifungal, antimalarial, antioxidant, anticancer, antiviral, and anti-inflammatory. There is still limited report about the biological activity of the anti-inflammatory effect of limonoids isolated from plants. Therefore, this study aimed to examine the effect of intact, deformed and rearranged limonoids as anti-inflammatory agents. The majority of anti-inflammatory investigations were evaluated by in vitro and in vivo assays of the isolated pure compounds and their derivatives. For the in vitro study, intact and C-ring seco limonoids showed a potent inhibitory effect against NO production. The in vivo analysis of Intact, C-seco, and AD-seco limonoids showed a potent effect based on the inhibition of pro-inflammatory cytokines expression, indicating their potency as anti-inflammatory agents.