Direct infusion ESI-IT-MS n alkaloid profile and isolation of tetrahydroharman and other alkaloids from Bocageopsis pleiosperma maas (Annonaceae) Elzalina R. Soares, a Felipe M. A. da Silva, a * Richardson A. de Almeida, a Bruna R. de Lima, a Francinaldo A. da Silva Filho, a Andersson Barison, b Hector H. F. Koolen, a,c Maria Lúcia B. Pinheiro a and Afonso D. L. de Souza a ABSTRACT: Introduction – The Annonaceae family is known as a promising abundant source of secondary metabolites, especially annonaceous acetogenins, terpenoids and isoquinoline-derived alkaloids. Although widely investigated from the phytochemical viewpoint, this family still presents some largely unexplored genera, e.g. the Bocageopsis. Objective – To investigate the alkaloid content of Bocageopsis pleiosperma Maas using direct infusion electrospray ionisation ion trap tandem mass spectrometry (ESI-IT-MS n ) analysis. Methodology – Dichloromethane extracts of aerial parts were subjected to acid–base partitioning to yield the alkaloidal fractions. These fractions were analysed by direct infusion into a (+)ESI-IT-MS n system. The alkaloidal fraction from the leaves was also obtained on a large scale and subjected to chromatographic separation. Results – The tentative MS n -based identification of alkaloids in leaves, twigs and trunk bark showed that aporphine alkaloids were restricted to the leaves and twigs, tetrahydroprotoberberine alkaloids were only found in the twigs and trunk bark while benzylisoquinoline alkaloids were found in the leaves, twigs and trunk bark. Chromatographic separation of the leaf alkaloidal fraction yielded the aporphine alkaloids nornuciferine, asimilobine and isoboldine, the β-carboline alkaloid tetrahydroharman and some mixtures containing benzylisoquinoline and aporphine alkaloids, all described for the first time in the Bocageopsis genus. Furthermore, tetrahydroharman has not previously been reported in the Magnoliales order. Conclusion – Direct infusion ESI-IT-MS n analysis of alkaloids allowed fast recognition of alkaloidal classes previously reported in the Annonaceae family, aiding the chromatographic step and allowing a selective isolation of compounds previously not identified in the Bocageopsis genus. Copyright © 2015 John Wiley & Sons, Ltd. Additional supporting information may be found in the online version of this article at the publisher’s website. Keywords: Alkaloid profiling; Bocageopsis pleiosperma; isoquinoline-derived alkaloids; tetrahydroharman Introduction Annonaceae, the largest family of the Magnoliales order, is currently composed of 2500 species distributed in 130 genera with about 900 species (40 genera) in the Neotropical region (Richardson et al., 2004). In Brazil 260 endemic species are catalogued and distributed in 26 genera (Maas et al., 2001), with several species being used in traditional medicine (Mahiou et al ., 2000; Frausin et al., 2014). Chemically this family is characterised by the presence of terpenoids, annonaceous acetogenins and isoquinoline-derived alkaloids, the latter being the most recurrent (Leboeuf et al., 1982). Diverse alkaloids including benzylisoquinolines, tetrahy- droprotoberberines, aporphinoids and β-carboline alkaloids have been reported in this family (Leboeuf et al., 1982; Costa et al., 2006). Investigations using tandem mass spectrometry (MS n ) demonstrated that benzylisoquinoline alkaloids possess a set of key fragmentation patterns, from which it is possible to determine the substituents in the benzyl and the isoquinoline moieties (Schmidt et al., 2005); aporphines have fragmentation patterns that are useful for the characterisation of different substituent groups on the main aporphine skeleton (mainly in rings A and D) (Stévigny et al ., 2004); and tetrahydroprotoberberine alkaloids fragment through a retro-Diels–Alder (RDA) pattern, which enables the determination of the A and D rings substitutions (Shim et al., 2013). Thus, the tentatively characterisation of these compounds * Correspondence to: Felipe M. A. da Silva, Department of Chemistry, Federal University of Amazonas, Av. Gen. Rodrigo Octávio, 6200, CEP 69077–000, Manaus-AM, Brazil. E-mail: felipesaquarema@bol.com.br; felipemas@ufam.edu.br a Department of Chemistry, Federal University of Amazonas, 69077-000, Manaus, AM, Brazil b NMR Center, Federal University of Paraná, 81531-990, Curitiba, PR, Brazil c Institute of Chemistry, University of Campinas, 13083-970, Campinas, SP, Brazil Phytochem. Anal. 2015, 26, 339–345 Copyright © 2015 John Wiley & Sons, Ltd. Research article Received: 17 October 2014, Revised: 15 April 2015, Accepted: 21 April 2015 Published online in Wiley Online Library: 24 June 2015 (wileyonlinelibrary.com) DOI 10.1002/pca.2568 339