Two new chlorine-containing polyoxygenated seco-cyclohexenes, albanols A (1) and B (2), along with the oxepinone metabolite grandiuvarone (3) were isolated from the endemic Philippine Annonaceae plant Uvaria alba. Both new compounds exhibited modest antitubercular activity. Compound 1 showed cytostatic activity (ranging from 1-50 μM) against HeLa cells and weak antiproliferative activity against HUVEC and K-562 cells with GI values of 106 and 81 μM, respectively.

A Smiles-type radical rearrangement induced by visible-light-mediated decarboxylation of ω-aryl- N-(acyloxy)phthalimides was developed, giving rise to pharmacologically important substance classes: phenylethylamine derivatives, dihydroisoquinolinones, and benzoazepinones were synthesized on the basis of readily available benzoic acids or benzaldehydes and β- or γ-amino acids. This methodology facilitates the synthesis of enantiopure D-amphetamine and of precursors of capsazepinoid bronchodilators.

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Hetero- and carbocyclic anellated cyclopropanes were converted in one step by a visible light induced photooxidation to their corresponding polycyclic endoperoxides, which show promising antimalarial activity.

Phaeanthus ophthalmicus (Roxb. ex G.Don) J.Sinclair (previously known as P. ebracteolatus (Presl) Merr) is a Philippine medicinal plant occurring as evergreen shrub in the lowland forests of Luzon islands. It is used traditionally by Filipinos to treat bacterial conjunctivitis, ulcer and wound infections. Based on previous investigations where cyclooxygenase-2 (COX-2) functions as immune-linked factor in infectious sensitivities to bacterial pathogens by triggering pro-inflammatory immune-associated reactions, we investigated the antimicrobial and COX inhibitory activities of the extracts and tetrahydrobisbenzylisoquinoline alkaloids of P. ophthalmicus in vitro and in silico to validate its ethnomedicinal uses. Thus, the dichloromethane–methanol (DCM–MeOH) crude extract and alkaloid extracts exhibiting antibacterial activities against drug-resistant bacterial strains such as methicillin-resistance Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), Klebsiella pneumoniae + CRE and Pseudomonas aeruginosa + MBL afforded (+)-tetrandrine (1) and (+)-limacusine (2) as the major biologically active tetrahydrobisbenzylisoquinoline alkaloidal constituents after purification. Both tetrahydrobisbenzylisoquinoline alkaloids 1 and 2 showed broad spectrum antibacterial activity with strongest inhibition against the Gram-negative bacteria MβL-Pseudomonas aeruginosa Klebsiella pneumoniae + CRE. Interestingly, the alkaloid limacusine (2) showed selective inhibition against ovine COX-2 in vitro. These results were ascertained by molecular docking and molecular dynamics simulation experiments where alkaloid 2 showed strong affinity in the catalytic sites of Gram-negative bacterial enzymes P. aeruginosa elastase and K. pneumoniae KPC-2 carbapenemase (enzymes involved in infectivity mechanisms), and of ovine COX-2. Overall, our study provides credence on the ethnomedicinal use of the Philippine medicinal plant P. ophthalmicus as traditional plant-based adjuvant to treat bacterial conjunctivitis and other related infections. The antibacterial activities and selective COX-2 inhibition observed for limacusine (2) point to its role as the biologically active constituent of P. ophthalmicus. A limited number of drugs with COX-2 inhibitory properties like celecoxib also confer antibacterial activity. Thus, tetrahydrobisbenzyl alkaloids, especially 2, are promising pharmaceutical inspirations for developing treatments of bacterial/inflammation-related infections.

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Background: Electrophilic compounds bearing Michael acceptors present great promise in anticancer drug discovery. Methods: Drawing inspirations from cytotoxic Piper lactam alkaloids, twelve N-acylated butyro- and valerolactams were prepared and evaluated for antiproliferative and cytotoxic activities against the normal human umbilical vein endothelial cells (HUVEC), chronic human myeloid leukemia cells (K- 562), and Henrietta Lacks (HeLa) cells used as model cell lines. Molecular docking of bioactive derivatives was performed against tyrosine kinase. Results: Results of the MTT assay showed the crotonylated (5) and nitro-containing cinnamoyl (8) butyrolactams, and, the crotonylated (10), trifluoromethylated (13), and chlorinated (14) cinnamoyl valerolactam derivatives as the most antiproliferative against human myeloid leukemia cells. The trifluoromethylated cinnamoyl valerolactam (13) displayed the best selectivity on K-562 cells. Molecular docking studies of 13 against tyrosine kinase provided evidence as tyrosine kinase inhibitor, having comparable binding energy and receptor interaction with imatinib. Conclusion: The presence of electrophilic N-acrylic moieties contributes to the potential of a compound as inspiration to develop anti-leukemia drugs.

Combining palladium catalyzed reactions in one-pot reactions represents an efficient and economical use of catalyst. The Suzuki-Miyaura cross-coupling has been proven to be a reaction which can be combined with other palladium catalyzed reactions in the same pot. This mini-review will highlight some of the latest examples where Suzuki-Miyaura cross-coupling reactions have been combined with other palladium catalyzed reactions in one-pot reaction. Predominantly, examples with homogeneous reaction conditions will be discussed in addition to a few examples from the authors where Pd/C have been used as a catalyst.