Several new pyrazolo[3,4‐b]pyridines were obtained from the reaction of 5‐amino‐1‐aryl‐3‐methylpyrazoles 1 with β‐dimemylaminopropiophenones 2 in pyridine. The structure elucidation of 4,5‐dihydropyrazolo[3,4‐b]pyridines 3 is based on nmr measurements and X‐ray diffraction. The treatment of compounds 3 with N‐bromosuccinimide led to the formation of pyrazolo[3,4‐b]pyridines 4.

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The novel melampolides (11R)-11,13-dihydro-schkuhriolide (7), (11S)-11,13-dihydro-schkuhriolide (8), and schkuhrioidiol (11), along with the known constituents, frutescin (1), schkuhriolide (2), frutescinic acid (4), allo-schkuhriolide (5), and epoxyschkuhriolide (6) were isolated from the aerial parts of Schkuhria schkuhrioides. The structures of the new compounds were determined by spectroscopic methods. Compounds 1, 2, 4, 5, and 6 displayed no significant cytotoxic or antimicrobial activities.

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