Crystal and molecular structure of grayanotoxin - I, C22H36O7

Biological and chemical guided isolation of 3,4-secograyanane diterpenoids from the roots of Pieris formosa

“…S4-S6 †), characteristic of the highly hydroxylated grayanane diterpenoids. Finally, seventeen new 3,4-secograyanoids (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17), together with seven known 3,4secograyanoids (18)(19)(20)(21)(22)(23)(24), were isolated from the fractions D1a, D2a, D2b, E1a, E1b, and E2a by a combination of different chromatographic methods. Acetic acid-induced writhing test showed that compounds 1, 2, 4-8, 10-13, and 16-24 exhibited signicant analgesic activity at 5.0 mg kg À1 (ip).…”

“…14 In previous phytochemical investigations of P. formosa, een grayananes and three diterpenes with an unusual carbon skeleton were isolated and characterized, and most compounds were found to exhibited an analgesic effect. 15,16 In our on-going efforts, biological and chemical guided fractionation led to the isolation of seventeen new 3,4-secograyananes (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17), together with seven known 3,4-secograyanoids (18)(19)(20)(21)(22)(23)(24)) (see Fig. 1).…”

Structural Diversity and Biological Activity of the Genus Pieris Terpenoids

“…Their monomers were initially isolated from the leaves of Leucothoe grayana by Tallent et al in 1954 . In 1970, their stereochemical structures were determined unambiguously by Narayanan et al through X-ray crystal analysis . Grayanotoxin I has the capacity to depolarize isolated cardiac tissues from dogs as well as guinea pigs by stimulating or opening sodium (Na + ) channels. , Grayanotoxin III exerts neurotoxic effects by activating voltage-dependent Na + channels in the excitatory and inhibitory nerve terminals of rat ventromedial hypothalamic neurons. , Asebotoxin I ( 3 ), VI ( 8 ), and X ( 5 ) (Figure ) from the flowers of a well-known poisonous tree, P. japonica , were identified on the basis of their chemical and physical evidence.…”

A case of human poisoning by grayanotoxins following honey ingestion: elucidation of the toxin profile by mass spectrometry

“…Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions Introduction Grayanotoxins (GrTx) are formed by the plant family Ericaceae, for instance by genera of Rhododendron, Pieris (Andromeda), Leucothoe, Craibiodendron, Lyonia or Kalmia (Scott et al 1971;Burke & Doskotch 1990;Teuscher & Lindequist 1994;Kron et al 2002;Qiang et al 2011;Li et al 2013). These secondary metabolites are diterpenes with a tetracyclic A-nor-B-homo-ent-kaurane skeleton called grayanane or andromedane, a polyhydroxylated cyclic hydrocarbon with a 5/7/6/5 ring structure (Wood et al 1954;Tallent et al 1957;Narayanan et al 1970;Burke & Doskotch 1990;Li et al 2013) (Figure 1). In addition to the GrTx, related toxins such as asebotoxins, rhodojaponins, rhodomolleins, kalmitoxins, lyoniatoxins and craiobiotoxins are formed by different substitution of the skeleton (Figure 1 and Table 1).…”