NMR studies of inclusion complexation of the pyrrolizidine alkaloid retronecine and p-sulfonic acid calix[6]arene

Syntheses and reactivity of calixarenes functionalized at meso positions

“…Since the investigation of calixarenes dealing with their syntheses, reactivity and a large variety of applications is very intense, [55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70] only selected examples of considered compounds are described in this review.…”

Calixarene-Based Receptors for Molecular Recognition

“…Supramolecular systems are promising as detoxificant agents by decreasing the bioavailability of toxic compounds in biological environments. Silva et al 57 have observed the interactions between p -sulfonic acid calix [6]arene 10 and retronecine, a toxic pyrrolizidine alkaloid, by NMR techniques. NMR results showed that a strong association between retronecine and 10 was observed as a result of interactions established between the amine and/or hydroxyl groups of the alkaloid retronecine and the SO 3 H group of compound 10 ( Figure 6).…”

Applications of calixarene nano-baskets in pharmacology

“…Retronecine as a toxic pyrrolizidine is synthesized by plants from the genus Senecio. da Silva et al [64] isolated the retronecine from Senecio braziliensis shoots with an overall yield of 4% in relation to the total alkaloid content and studied the inclusion complexation of p-sulfonic acid calix [6]arene towards retronecine by NMR techniques, which obtained the detailed information about the interactions in aqueous solution. They suggested that one moiety of retronecine was inside the p-sulfonic acid calix [6]arene.…”

“…Fig. 15 The proposed complex topology for inclusion of p-sulfonic acid calix [6]arene towards retronecine [64] Fig. 16 Illustration of the GKP(D)V peptide attached to the calix [4]arene compound via a PEG-350 tether link, which was then coated onto glass [65] J Incl Phenom Macrocycl Chem (2012) 73:1- 15 11 Phenothiazines occur in various antipsychotic and antihistaminic drugs and are used as inodilators in congestive heart failure, acting upon the type I calcium/calmodulin dependent phosphodiesterase.…”