Peperomia Piperaceae

Dihydroxy-3,6,7,4 -tetramethoxyflavone 8-Neohesperidoside Peperomia pellucida Piperaceae 460... 

Fig. 1.30. Diurnal acid fluctuation in Didieriaceae Did=Allmudia), Portulacaceae (Port=Anacampseros), Cucurbitaceae (Cuc=Xerosicyos), and Piperaceae Pip = Peperomia)...

The first example of this section by Batista et ah deals with the determination of the AC of the enantiomers of the trypanocidal chromane peperobtusin A 5 (Figure 53.17), isolated from Peperomia obtusifolia (Piperaceae), using VCD spectroscopy and DFT calculations. In a similar fashion to what was described for compound 2 in the section 53.2.5, DFT calculations revealed the bulky prenyl chain at C2 to adopt preferentially the axial position, contrary to the assumption of the equatorial positioning of the chromane helicity rule, within the half-chair conformation. 

Batista JM, Batista ANL, Rinaldo D, Vilegas W, Cass QB, Bolzani VS, Kato MJ, L6pez SN, Furlan M, Nafie LA. Absolute configuration reassignment of two chromanes from Peperomia ohtusifolia (Piperaceae) using VCD and DFT calculations. Tetrahedron Asymm. 2010 21(19) 2402-2407. 

Batista JM, Lopez SN, da Silva Mota J, Vanzolini KL, Cass QB, Rinaldo D, Vilegas W, da Silva Bolzani V, Kato MJ, Furlan M. Resolution and absolute configuration assignment of a natural racemic chromane from Peperomia ohtusifolia (Piperaceae). Chirality 2009 21(9) 799-801. 

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