No abstract

A considerable number of natural products have been published in recent years with misassigned structure, even though they had been correctly elucidated in the past. The availability of databases containing revised structures can prevent the amplification of errors in structural elucidation. NAPROC-13, a dereplication tool based on the 13C chemical shift, has been used to search for substances that, possessing the same chemical shifts, have been described with different structures. The correct structure of these different structural proposals is verified by computational chemistry. This paper reports the structural revision of nine triterpenoids following this methodology.

The aim of this study was to analyze the chemical components and evaluate the biological activity of the extracts from the leaves Kalanchoe pinnata and Kalanchoe daigremontiana, which are cultivated in the province of Chiriqui, Republic of Panama. Phytochemicals components, antioxidant and anti-inflammatory activities were studied. The composition of the obtained petroleum ether, ethanol and aqueous extracts was analyzed by phytochemical screening. The antioxidant activity of the extracts was studied using three in vitro model systems (DPPH radical scavenging assay, nitric oxide radical scavenging assay, and superoxide radical scavenging activity). The anti-inflammatory activity of these species was studied using an in vivo model (ʎ-carrageenan-induced paw edema in rats). Phytochemical analysis of the extracts showed the presence of alkaloids, steroids, triterpenes, flavonoids, phenolic compounds, saponins and glycosides. The greatest radical inhibitory effect was observed in the DPPH model where the ethanolic extracts of both species developed a concentration-dependent inhibitory effect, the K. pinnata extract reached a maximum inhibitory effect of 49.5 ± 5.6% (2000

Context: Since there is still a great need to search for plant species with antinociceptive and anti-inflammatory activities, Diploptropis purpurea (Rich.) Amshoff (Fabaceae) is studied for the first time. Objective: This evaluates the analgesic and anti-inflammatory activities of the stem methanol extract of Diplotropis purpurea (MEDP). Material and methods: The anti-inflammatory and analgesic effects of MEDP of D. purpurea were evaluated in vivo . The antinociceptive activity was assessed in CD1 male mice were treated by oral gavage with 500 mg/kg of MEDP 30 min before submitting to acetic acid-induced abdominal writhing, hot-plate, and formalin tests. Paws oedema induced by carrageenan, histamine or serotonin were performed in male Sprague–Dawley rats to determinate the anti-inflammatory activity. Results: Oral administration of MEDP produced significant antinociceptive effects on the inflammatory phase in the formalin test [12.0 s versus 72.5 s in carboxymethyl cellulose (CMC) control group]. MEDP produced an analgesic effect in the hot-plate model, although the effect was modest compared to tramadol (40 and 60%, respectively). The oral administration of MEDP in a dose of 500 mg/kg showed maximum inhibition (75.1%) after 0.5 h in carrageenan-induced oedema, but it did not modify histamine or serotonin-induced oedemas. Discussion and conclusion: In the peripheral nociception model, acetic acid-induced abdominal writhing, the MEDP did not show a protective effect, but its analgesic effects were evident in the inflammatory phase of the formalin test and in the hot-plate model. These results show that the anti-inflammatory effect was accompanied by a reduction in the perception of painful stimuli.

Carvone is one of the most versatile synthons in organic synthesis. It has been used as starting material for a huge number of organic syntheses of natural products with interesting biological activities. This manuscript communicates the antioxidant activity against superoxide of carvone and several derivatives.