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Gallic acid converts atmospheric oxygen into hydrogen peroxide, which is able to oxidize arylboronic acids as a proof of concept of sustainable oxidations. Moreover, tannic acid and grape pomace extract are also able to perform oxidations with air. Therefore this work unleashes an alternative method for reutilization and valorization of bio-wastes rich in tannins.

Several preparations were obtained from the aerial parts of predomesticated Lavandula luisieri, including the essential oil and ethanolic, hexane, and ethyl acetate extractives. Additionally, pilot plant vapor pressure extraction was carried out at a Several preparations were obtained from the aerial parts of predomesticated Lavandula luisieri, including the essential oil and ethanolic, hexane, and ethyl acetate extractives. Additionally, pilot plant vapor pressure extraction was carried out at a pressure range of 0.5–1.0 bar to give a vapor pressure oil and an aqueous residue. A chemical study of the hexane extract led to the isolation of six necrodane derivatives (1, 2, and 4–7), with four of these (1, 2, 5, and 7) being new, as well as camphor, a cadinane sesquiterpene (9), tormentic acid, and ursolic acid. The EtOAc and EtOH extracts contained a mixture of phenolic compounds with rosmarinic acid being the major component. Workup of the aqueous residue resulted in the isolation of the necrodane 3 and (1R*,2S*,4R*)-p-menth-5-ene-1,2,8-triol (8), both new natural compounds. The structures of the new compounds were established based on their spectroscopic data. The phytotoxic and nematicidal activities of these compounds were evaluated.

Gallic acid efficiently catalyses radical arylations in water–acetone at room temperature. This methodology proved to be versatile and scalable. Therefore, it constitutes a greener alternative to arylation. Moreover, considering that gallic acid is an abundant vegetable tannin, this work also unleashes an alternative method for the reutilisation of bio-wastes.

The Himalayan mountain range has been the locus of some of the largest continental earthquakes, including the 2015 magnitude 7.8 Gorkha earthquake. Competing hypotheses suggest that Himalayan topography is sustained and plate convergence is accommodated either predominantly on the main plate boundary fault, or more broadly across multiple smaller thrust faults. Here we use geodetic measurements of surface displacement to show that the Gorkha earthquake ruptured the Main Himalayan Thrust fault. The earthquake generated about 1 m of uplift in the Kathmandu Basin, yet caused the high Himalaya farther north to subside by about 0.6 m. We use the geodetic data, combined with geologic, geomorphological and geophysical analyses, to constrain the geometry of the Main Himalayan Thrust in the Kathmandu area. Structural analyses together with interseismic and coseismic displacements are best explained by a steep, shallow thrust fault flattening at depth between 5 and 15 km and connecting to a mid-crustal, steeper thrust. We suggest that present-day convergence across the Himalaya is mostly accommodated by this fault—no significant motion on smaller thrust faults is required. Furthermore, given that the Gorkha earthquake caused the high Himalayan mountains to subside and that our fault geometry explains measured interseismic displacements, we propose that growth of Himalayan topography may largely occur during the ongoing post-seismic phase.

The objective of this study was the characterization and valorization of the essential oil from a domesticated Artemisia absinthium population (Teruel, Spain), and its comparison with another one (Sierra Nevada, Spain) undergoing the domestication process. These populations are being experimentally cultivated in the same field since 2008. We studied their biomass and essential oil production (Clevenger hydrodistillation, HD and semi-industrial vapor-pressure, VP). The domesticated population showed lower chemical variation and higher biomass and essential oil yields, allowing for the registration of a new plant variety. The observed variations in oil composition (HD, VP) between the two populations were mostly quantitative. The oils were characterized by the presence of cis-epoxyocimene, (-)-. cis-chrysanthenol, chrysanthenyl acetate, linalool and trans-caryophyllene. The insect antifeedant (. Leptinotarsa decemlineata, Spodoptera littoralis, Myzus persicae and Rhopalosiphum padi) and antifungal (. Fusarium spp. and Botrytis cinerea) effects of their oils were also tested. All VP extracts showed strong antifungal effects and the active antifungal compounds have been identified.

The microwave‐assisted imidazole‐catalyzed transformation of propargyl vinyl ethers (PVEs) into multisubstituted salicylaldehydes is described. The reaction is instrumentally simple, scalable, and tolerates a diverse degree of substitution at the propargylic position of the starting PVE. The generated salicylaldehyde motifs incorporate a broad range of topologies, spanning from simple aromatic monocycles to complex fused polycyclic systems. The reaction is highly regioselective and takes place under symmetry‐breaking conditions. The preparative power of this reaction was demonstrated in the first total synthesis of morintrifolin B, a benzophenone metabolite isolated from the small tree Morinda citrifolia L. A DFT study of the reaction was performed with full agreement between calculated values and experimental results. The theoretically calculated values support a domino mechanism comprising a propargyl Claisen rearrangement, a [1,3]‐H shift, a [1,7]‐H shift (enolization), a 6π electrocyclization, and an aromatization reaction.

The different factors that control the alkene Prins cyclization catalyzed by iron(III) salts have been explored by means of a joint experimental–computational study. The iron(III) salt/trimethylsilyl halide system has proved to be an excellent promoter in the synthesis of crossed all‐cis disubstituted tetrahydropyrans, minimizing the formation of products derived from side‐chain exchange. In this iron(III)‐catalyzed Prins cyclization reaction between homoallylic alcohols and non‐activated alkenes, two mechanistic pathways can be envisaged, namely the classical oxocarbenium route and the alternative [2+2] cycloaddition‐based pathway. It is found that the [2+2] pathway is disfavored for those alcohols having non‐activated and non‐substituted alkenes. In these cases, the classical pathway, via the key oxocarbenium ion, is preferred. In addition, the final product distribution strongly depends upon the nature of the substituent adjacent to the hydroxy group in the homoallylic alcohol, which can favor or hamper a side 2‐oxonia‐Cope rearrangement.

After 20 years of quiescence, Fogo volcano erupted in November 2014. The eruption produced fast‐moving lava flows that traveled for several kilometers and destroyed two villages. This event represents the first episode of significant surface deformation imaged by the new European Space Agency's Sentinel‐1 satellite in its standard acquisition mode, Terrain Observation by Progressive Scans (TOPS), which differs from that of previous synthetic aperture radar (SAR) missions. We perform a Bayesian inversion of Sentinel‐1 TOPS SAR interferograms spanning the eruption and accurately account for variations in the TOPS line‐of‐sight vector when modeling displacements. Our results show that magma ascended beneath the Pico do Fogo cone and then moved laterally toward its southwestern flank, where the eruptive fissure opened. This study provides important insights into the inner workings of Fogo volcano and shows the potential of Sentinel‐1 TOPS interferometry for geophysical (e.g., volcano monitoring) applications.

The development of peptide libraries by site-selective modification of a few parent peptides would save valuable time and materials in discovery processes but still is a difficult synthetic challenge. Herein, we introduce natural hydroxyproline as a convertible unit for the production of a variety of optically pure amino acids, including expensive N-alkyl amino acids, homoserine lactones, and Agl lactams, and to achieve the mild, efficient, and site-selective modification of peptides. A domino process is used to cleave the customizable Hyp unit under mild, metal-free conditions. Both terminal and internal positions can be modified, and similar customizable units can be differentiated. The resulting products possess two reactive chains which can be manipulated independently. The versatility and scope of this process is highlighted by its application to the ligation of two peptide chains, and the generation of peptides with several chains and peptides with conformational restrictions.

Tanzawaic acids M (1), N (2), O (3) and P (4) and the known tanzawaic acids B (5) and E (6), have been isolated from an extract of a cultured marine-derived fungus (strain CF07370) identified as a member of the genus Penicillium. The structures of 1–4 were determined based on spectroscopic evidence. The antimicrobial and cytotoxic activities of compounds 1–6 were evaluated.