In the review period, 97 new representatives of Stemona alkaloids were described, bringing the total reported so far to 139. In this review, we discuss their isolation, structural elucidation, structural classification, biological activities, semi-synthesis and total syntheses. These alkaloids are classified into seven groups displaying either a pyrrolo[1,2-a]azepine or a pyrido[1,2-a]azepine core, and a miscellaneous group comprising those alkaloids without these structural motifs, together with those that are the sole representative of a new group. It displays a ring A pyrrole unit, and its relative stereochemistry resembles that of tuberostemonine J (5), except for H-18 which is proposed to be aoriented in epi-bisdehydroneotuberostemonine J (10) while it is b-oriented in tuberostemonine J (5) and in most of the other Stemona alkaloids bearing the a-methyl-g-butyrolactone moiety attached to C-3. Its absolute chemical structure was claimed to have been established by X-ray crystallographic analysis. 1 9a-Bisdehydrotuberostemonine (11) also displays a pyrrole ring and it was isolated from the roots of S. tuberosa. 15 Its structure was assigned as the 9a epimer of bisdehydrotuberostemonine, also known as didehydrotuberostemonine, 4 by Fig. 2 Stemona alkaloids of the stenine group (1-14).

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On-line monitoring of Stille reactions was performed via direct infusion electrospray ionization mass spectrometry (ESI-MS) and its tandem version (ESI-MS/MS). When operated in the positive ion mode, ESI(+)-MS was able to transfer, directly from solution to the gas phase, the species involved in all main steps of a Stille reaction, that is, the catalytically active palladium species Pd(PPh3)2, in its molecular ion form as well as the key cationic Pd(II) intermediates, including cyclic IPd-(CH2CH)Sn species. When searching for anionic species, ESI(-)-MS monitoring showed I- as the only anion detectable in the reaction medium. A detailed catalytic cycle for a Stille reaction was elaborated in which reaction intermediates and the previously elusive catalytically active Pd(0) species are shown in association with the respective ionic species intercepted by ESI-MS and further characterized by ESI-MS/MS.

A preparação de uma série de β-enamino cetonas e ésteres empregando a metodologia de reações em suporte sólido associada à irradiação de microondas é descrita. As reações dos compostos β-dicarbonílicos cíclicos, acíclicos e α-cloro-substituídos, frente a aminas primárias ou aos acetatos de amônio correspondentes, foram efetuadas usando K-10 como suporte sólido e forno de microondas doméstico como fonte de irradiação, obtendo-se os β-enamino compostos com ótimos rendimentos.The preparation of β-enamino ketones and esters using the methodology of the reactions on solid support coupled with microwave irradiation is described. The reaction of cyclic, acyclic and α-chloro-substituted β-dicarbonyl compounds with amines or their corresponding ammonium acetates was carried out using K-10 as solid support and a domestic microwave oven as the radiation source to give β-enamino carbonylic compounds in good yields.

Let f be a modular form of weight k and Nebentypus ψ. By generalizing a construction of [20], we construct a p-adic L-function interpolating the special values of the L-function L(s, Sym 2 (f ) ⊗ ξ), where ξ is a Dirichlet character. When s = k − 1 and ξ = ψ −1 , this p-adic L-function vanishes due to the presence of a so-called trivial zero. We give a formula for the derivative at s = k −

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Let p ≥ 3 be a prime and F a totally real number field. Let f be a Hilbert cuspidal eigenform of parallel weight 2, trivial Nebentypus and ordinary at p. It is possible to construct a p-adic L function which interpolates the complex L-function associated with the symmetric square representation of f . This p-adic L-function vanishes at s = 1 even if the complex L-function does not. Assuming p inert and f Steinberg at p, we give a formula for the p-adic derivative at s = 1 of this p-adic L-function, generalizing unpublished work of Greenberg and Tilouine. Under some hypotheses on the conductor of f we prove a particular case of a conjecture of Greenberg on trivial zeros.

Soient F F un corps de fonctions sur F q \mathbb {F}_q , A A l’anneau des fonctions régulières hors d’une place ∞ \infty et p \mathfrak {p} un idéal premier de A A . En premier lieu, nous développons la théorie de Hida pour les formes modulaires de Drinfeld de rang r r qui sont de pente nulle pour l’opérateur de Hecke U π \mathrm {U}_{\pi } convenablement défini. En second lieu, nous montrons en pente finie l’existence de familles de formes modulaires de Drinfeld variant continûment selon le poids. En troisième lieu, nous prouvons un résultat de classicité: une forme modulaire de Drinfeld surconvergente de pente suffisamment petite par rapport au poids est une forme modulaire de Drinfeld classique.