Molecular evolutionary lines in the formation of indole alkaloids derived from secologanin

Abstract

Generation of the strictosidine → stemmadenine → ellipticine/olivacine and the strictosidine → vincadifformine→ rhazinilam/rhazinal molecular evolutionary lines indicated the multistep bioorganic interactions in the frame of indole alkaloids derived from secologanin. Narrow structural elements, detailed chemotaxonomic data and standard organic reaction mechanisms, together with computer search of the DNP databases contributed considerably to the knowledge of the chemical background of this important class of natural products and detected several longrange electronic connections between the nitrogen atoms in these molecules.

Chemotaxonomy: The Role of Phytochemicals in Chemotaxonomic Delineation of Taxa

“…For instance, the indole alkaloids contain indole as the parent base and more than 2,500 indole alkaloids were isolated mainly from three plant families, Rubiaceae, Loganiaceae and Apocynaceae. The indole is formed from two building blocks secologanin and tryptamine or tryptophane through a single precursor, strictosidine [33]. This suggests a relationship between these families [33,34].…”

“…The indole is formed from two building blocks secologanin and tryptamine or tryptophane through a single precursor, strictosidine [33]. This suggests a relationship between these families [33,34]. Other indole alkaloids like physostigmine obtained from Physostigma venenosum (family Leguminosae) [35], yohimbine from Rauwolfia serpentina (family Apocyanaceae) [36] and Corynanthe yohimbe (family Rubiaceae) [37] and Vinblastine from Vinca rosea (family Apocyanaeae) [38].…”

Privileged Biorenewable Secologanin‐Based Diversity‐Oriented Synthesis for Pseudo‐Natural Alkaloids: Uncovering Novel Neuroprotective and Antimalarial Frameworks

“…Secologanin ( 1 , Scheme 1B), the most significant representative of iridoids, is a special type of naturally occurring monoterpenoid glucoside [10] . It is the precursor of thousands of existing indoles, isoquinolines, and related alkaloids with a huge diversity of chemistry and biological activities, [11] including impressive therapeutic agents such as vinblastine, quinine, and reserpine (Scheme 1B). Due to the biochemical significance in monoterpenoid indole alkaloid (MIA) biosynthesis, decades of investigation efforts have been devoted to secologanin‐related research.…”

“… Biosynthetic pathway disclosure: [12] Continuous research on secologanin biosynthesis has allowed the entire anabolic pathway elucidated in Catharanthus roseus , which consists of 10 enzymes starting from isopentenyl pyrophosphate (IPP) [12e] Chemical and biological modification: [13] Considerable efforts have been contributed to the preparation of secolgoanin, [13a] its analogues, [13b–f] and secologanin‐derived natural products [11–13] Biogenetic research probe: [14] Secolganin has been used as a substrate for strictosidine synthase [14a–e] and deacetylisoipecoside synthase [14f] as well as metabolic pathway study of plant terpenoid indole alkaloids [14g–k] …”

“…Chemical and biological modification: [13] Considerable efforts have been contributed to the preparation of secolgoanin, [13a] its analogues, [13b–f] and secologanin‐derived natural products [11–13] …”