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: This paper presents a short review of synthetic approaches aiming to synthesise (+)-Grandisol, the main constituent of grandlure, a pheromone mixture released by the boll weevil which is proven to exhibit significant biological activity. (+)-Grandisol 1 is among the components of the male-produced pheromone of the boll weevil Anthonomuns grandis, an important pest of cotton crops in Mesoamerica (from the south USA to Argentina). As a result of its biological activity and unique structure, several synthetic approaches have been reported. The aim is to explore remarkable methodologies towards the synthesis of (+)-Grandisol 1. Several methodologies have been applied towards the synthesis of (+)-Grandisol 1, including classical methods for cyclobutane ring construction, which promoted substantial improvements to access this pheromone, as well as better comprehension of its biological profile.

Synthesis and SAR investigation of 2-guanidinoquinazolines, initially identified in a high content screen for selective STAT3 pathway inhibitors, led to a more potent analog (11c) that demonstrated improved anti-proliferative activity against a panel of HNSCC cell lines.

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Abstract:The aqueous tin-mediated Barbier reaction affords good to excellent yields and moderate syn diastereoselectivity under basic and acidic conditions. The high yields and stereoselectivity observed in the case of o-substituted aldehydes suggest a cyclic organotin intermediate or transition state in K 2 HPO 4 solution. A practical and efficient aqueous tin allylation of methoxy-and hydroxybenzaldehydes can be carried out in HCl solution in 15 minutes to afford the corresponding homoallylic alcohols in high yields. Aliphatic aldehydes give moderate to excellent yields with reaction times ranging from 30 to 60 minutes. Under these conditions, crotylation gives exclusively the γ-product and the syn isomer is formed preferentially. For 2-methoxybenzaldehyde, an equilibration of the isomers to a syn/anti ratio of 1:1 can be observed after several hours. Control experiments with radical sources or scavengers give no support for radical intermediates. NMR studies suggest a mechanism involving an organotin intermediate. The major organotin species formed depends on the reaction medium and the reaction time. The use of acidic solution reduces the reaction times, due to the acceleration of the formation of the allyltin(IV) species.

The article aims to analyze the progress of the evolution of cinnamic acid derivatives through a bibliographic review, describing the main synthetic routes in obtaining this class, as well as remarkable biological applications and application of the structure-activity relationship (SAR) as a strategy for design pharmacologically active molecules. The methodology used consists of reading and analyzing articles, whose approach is descriptive, with data being collected regarding the therapeutic potential of derivatives of cinnamic acid and its relationship with structural scaffolding, as well as the most widely used synthetic approaches. As a result, it was observed that cinnamic acid and its derivatives from natural sources can be synthesized in appreciable quantities with varied synthetic routes, as well as being candidates for therapeutic agents, since they have several therapeutic applications against diabetes, infectious and degenerative diseases, among others, in addition to presenting activity such as pest control, which has attracted the attention of academic and industrial researchers. These compounds are highly versatile since their activity is intrinsically associated with the mode of interaction between the structure and its molecular target. However, in nature they are obtained in small quantities, therefore, the development of new approaches of synthetic methodologies to obtain such compounds in substantial quantities and linked to medicinal chemistry can contribute to the development of very effective bioactive molecules in comparison with their precursors.

Electrochemical methods are considered useful tools for simulations of biological redox reactions. The activities of quinones depend on their bioreduction. Biologically active pterocarpanquinones LQB-149 (nitroderivative), 150 and 151 (bromo and chloroderivatives, respectively) were electrochemically investigated by cyclic voltammetry, differential pulse voltammetry, and in situ UV-Vis spectroelectrochemistry, in aprotic media (N,N-dimethylformamide (DMF) + tetra-N-butylammonium (TBAPF 6)). The data obtained regarding their reduction mechanisms, positive reactivity with oxygen and analysis of the electrogenerated intermediates were useful in explaining their biological outcomes. The appearance of bands at 397 and 480 nm, for the halogenated compounds, suggests the generation of transient quinonemethides (QM), electrophilic intermediates related to their activity. As an additional proof for the intermediacy of QM, in the redox processes, chemical reduction of LQB-150, in the presence of hexanethiol was performed and led to a thioalkylated quinone. For the nitroderivative, a broad band appeared at 432 nm, corresponding to the generation of the nitroradical anion, giving rise to a dianion diradical, after reduction at the second wave potential. Computational data correlate well with electrochemical experiments. Homogeneous electron transfer to oxygen, yielding reactive oxygen species, the generation of electrophilic species and the radical reactivity, explain partially the mechanism of biological action.

Descrevemos neste trabalho uma síntese curta e eficiente para o fragmento C1-C9 do potente agente antitumoral dictiostatina. Esta abordagem sintética inclui uma reação de epoxidação assimétrica de Sharpless seguida da abertura de epóxido nas condições de Myashita para introduzir os centros estereogênicos em C6 e C7 e uma reação de olefinação tipo Horner-Wadsworth-Emmons nas condições de Ando para construir a ligação com geometria /Z/do dieno 1,3-/Z/,/E/.We describe herein a short and efficient synthesis of the C1-C9 fragment of the potent antitumor agent dictyostatin. Notable features of this approach include a Sharpless asymmetric epoxidation followed by epoxide opening under Myashita's conditions to introduce the stereogenic centers at C6 and C7, and a Horner-Wadsworth-Emmons type reaction under Ando's conditions to construct the Z-double bond of the 1,3-(Z,E)-diene system.