Indole Alkaloids from Geissospermum reticulatum

Abstract

Ten indole alkaloids were isolated from Geissospermum reticulatum, seven (1-7) from the leaves and three (8-10) from the bark. Seven were aspidospermatan-type alkaloids (1-3, 5-9), including four (5-8) with a 1-oxa-3-cyclopentene group in their molecule, which we named geissospermidine subtype. Compounds 1-3, 5-8, and 10 had not been reported previously as natural products, while 4 and 9 were the known alkaloids O-demethylaspidospermine and flavopereirine. Their structures were determined by spectroscopic techniques including 1D and 2D NMR experiments (COSY, NOESY, HSQC, HMBC). Additionally, X-ray crystallographic analyses of 1, 2, and 6 were performed. Antiparasitic activities of the ethanolic and alkaloidal extracts and of the pure alkaloids were tested against Trypanosoma cruzi and Leishmania infantum. In general, the extracts exhibited selective action and were more active against Leishmania than against Trypanosoma. Alkaloid 4 was also very active against L. infantum.

Anti-promastigote Activity of the Amazon Plants

“…Various alkaloids presented anti-leishmanial activity [14][15][16]. In the present study we selected two species of this family, but any alkaloid was detected or isolated.…”

The plant extract ofPao pereirapotentiates carboplatin effects against ovarian cancer

“…It contains the alkaloid flavopereirine (also called PB-100), as well as many other kinds of indole and b-carboline alkaloids (Puiseux et al, 1959;Reina et al, 2012;Steele et al, 2002). According to anecdotal reports and some inconclusive evidence, flavopereirine or Pao may be of benefit for the treatment of malaria, cancer (including prostate cancer, glioblastoma and leukemia), HIV/AIDS, herpes simplex and hepatitis C (Beljanski & Beljanski, 1982;Beljanski et al, 1993;Bemis et al, 2009;Reina et al, 2012;Steele et al, 2002). However, Pao is commonly administered together with other herbal remedies, including ginkgo (Ginkgo biloba) and the indole alkaloid alstonine, which may have antipsychotic properties.…”

“…Later, Steele et al (2002) reported isolation of the three indole alkaloids and a b-carboline alkaloid flavopereirine from the bark of Geissospermum sericeum and their antiplasmodial activities. Reina et al (2012) reported seven indole alkaloids from the leaves and three from the bark of Geissospermum reticulatum and the antiparasitic activities of both the extract and each alkaloid. Mbeunkui et al (2012) isolated a new indole alkaloid along with four known indole alkaloids from the bark of Geissospermum vellosii and described their antiplasmodial activities.…”

Antioxidant Properties and Stability of Geissospermum Reticulatum Tinctures: Lag Phase ESR and Chemometric Analysis

“…There are some evidence showing that Geissospermum species demonstrate anti-malarial, antibacterial and nociceptive activities [1,7,8]. In our previous publication we reported that infusions, tinctures and extracts of Geissospermum reticulatum bark have potential to be used as good sources of bioactive compounds and exhibit antioxidant, cytotoxic and anti-proliferative properties [9].…”