The reaction of unsubstituted indole with different acylating agents such as acid chlorides, anhydrides, nitriles, and amino acid derivatives in the presence of Lewis acid is reported.The synthesis of 3-acylindoles has been the subject of considerable interest not only because they are used as synthetic intermediates in alkaloid synthesis but also because they have biological activities. 1 Three major synthetic methods have been employed to prepare this class of compounds using indole as the starting material: (1) acylation of indole Grignard reagents, [2][3][4] (2) acylation of N-protected indoles, 5 and (3) the Vilsmeier-Haack reaction. 2 There are also other methods based on acyl cation equivalents such as nitrilium salts 6 and dialkyl carbenium ions. 7,8 Another method, using N-(R-haloacyl)pyridinium salts, gives predominantly 3-acylindoles under controlled conditions, but it seems to be restricted to some very reactive R-haloacyl halides. 9 Each of these methodologies has merits and shortcomings that limit their scope and yield.

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Umsetzung des Pregnenolons (I) mit dem Amin (II) in CHQCIQ, CHCl3, THF oder Acetonitril führt zu dem erwarteten Fluorid (IIIb) und den Derivaten (IIIa)‐(V), wobei die Produkt‐ Verteilung von dem eingesetzten Lösungsmittel abhängig ist (Bildungsmechanismen werden vorgeschlagen).

Soil is an important and complex environmental compartment and soil contamination contributes to the pollution of aquifers and other water basins. A simple and low-cost experiment is described in which the mobility of three organic compounds in an artificial soil is examined using dry-column flash chromatography. The compounds were applied on top of the soil surface, and the column was irrigated with a dilute solution of calcium chloride that mimics rain. The compounds were detected in column drainage fractions using classic qualitative tests in which the intensity of the color produced is related to the concentration of the analyte. The experiment replicates a leaching system in which organic substances migrate through soil at distinct rates as a result of differences in partition constants and water solubility, properties that are related to structural features.

Utilizando um protocolo combinado de mecânica e dinâmica molecular, de baixo custo computacional, empregando-se a expressão e os parâmetros do campo de força OPLS-AA, foi possível reproduzir as principais características da primeira camada de hidratação de heterooligonucleotídeos de DNA em duplas hélices na conformação A (1DPL) e B (1DPN e 1ENN), conforme descrições cristalográficas com resolução atômica; nosso protocolo também reproduziu satisfatoriamente as características das primeiras camadas de hidratação de homo-oligonucleotídeos de DNA na conformação B [(AT) 12 e (CG) 12 ] obtidas em simulações por dinâmica molecular empregando-se protocolos mais longos e mais sofisticados. Um modelo preliminar da primeira camada de hidratação de oligonucleotídeos poderia ser útil para aqueles interessados em proceder cálculos mecânico-quânticos em sistemas cujas características de hidratação são desconhecidas em nível molecular ou, ainda, para refinamento de estruturas cristalográficas por comparação com padrões de difração experimentais.Using a computational low-cost protocol by combining molecular mechanics energy minimization and molecular dynamics employing the OPLS-AA force field, we were able to reproduce the main structural features of the first hydration shell of double-helix DNA heterooligonucleotides in the A (1DPL) and B-conformations (1DPN and 1ENN), whose coordinates are available with atomic resolution from crystallographic data. Our simple protocol also reproduced the main hydration patterns of DNA homo-oligonucleotides in the B-conformation [(AT) 12 and (CG) 12 ], obtained before by computer simulation using a longer and more sophisticated molecular dynamics protocol. A preliminary model of the first hydration shell of oligonucleotides may be very useful to those interested in performing quantum-mechanical calculations of systems where hydration features are unknown at the molecular level; the model may also be used by crystallographers during refinement steps.