Monoterpene Indole Alkaloids from Palicourea crocea

Abstract

Two new monoterpene indole alkaloids, named croceaines A (1) and B (2), were isolated from the leaves of Palicourea crocea. The structures of 1 and 2 were elucidated by means of spectroscopic methods.

Chemical constituents from leaves of Palicourea coriacea (Rubiaceae)

“…Others species have been reported to be neurotoxic to cattle, such as the species P. marcgravii, P. grandiflora and P. juruana [2]. The phytochemical study of Palicourea species allowed the identification of b-carbolines [3,4], the monoterpene indole [5,6] and pyrroloindoles [4,[7][8][9], alkaloids besides triterpenes [10,11], phenolic acids, coumarins [11] and a cyclic peptide [12]. P. coriacea, popularly known as ''douradinha,'' is used in the cerrado (savannah) of Brazil in a tea used to treat calculus in the kidney and urethra and kidney inflammations [13].…”

“…The collected fractions were analyzed by TLC and reunited in groups to afford (1, 116.0 mg), (2, 6.4 mg), (3, 7.6 mg) and a mixture (5.80 mg) of the isomers 3 (65.45%) and 4 (34.53%). and allantoin [14,22], respectively, by analysis and comparison of their spectral data with those in the literature (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11). Only the two compounds 5 and 6 have been identified in Palicourea genera.…”

Monoterpenoid indole alkaloids from Palicourea crocea

“…The HRESIMS data, which gave an [M+H] + peak at m/z 529.2180, corresponding to a molecular formula of C 27 H 32 N 2 O 9 , supported this conclusion. Indeed, comparison of [a] D , IR, UV, 1 H and 13 C NMR data of (1) with those for croceaine A, which was previously isolated from Palicourea crocea from Brazil (Dusman et al, 2004), established its identity.…”

“…(Rubiaceae) have been used in traditional medicine to treat cancer (Hartwell, 1971) and are well known for their toxicity towards animals (Gorniak et al, 1990;Tokarnia et al, 2000). Chemical investigations of various species have led to the isolation of alkaloids (do Nascimento et al, 2008;Valverde et al, 1999;Dusman et al, 2004;Ripperger, 1982), triterpenes (Bolzani et al, 1992;Achenbach et al, 1995;El Seedi, 1999), coumarins (El Seedi, 1999), phenolic acids El Seedi, 1999) and an anti-HIV macrocyclic peptide (Bokesh et al, 2001). Palicourea species appear to be closely related to those of the subgenus Heteropsychotria of the very large genus Psychotria L. (Rubiaceae) as evidenced by the presence of monoterpene indole alkaloid glucosides in both groups.…”

“…et Schultes from Trinidad. The Brazilian species has been studied before (Dusman et al, 2004). We report herein the isolation of two known monoterpene indole alkaloids, croceaine A (1), previously isolated from the Brazilian Palicourea crocea species (Dusman et al, 2004), and psychollatine (2), reported from Psychotria umbellata (Kerber et al, 2008), in addition to the new monoterpenoid indole alkaloid N-oxide, 3,4-dihydro-1-(1-b-Dglucopyranosyloxy-1,4a,5,7a-tetrahydro-4-methoxycarbonylcyclopenta[c]pyran-7-yl)-b-carboline-N 2 -oxide (3).…”