A highly efficient, two-step, one-pot synthetic strategy for amides and peptides was developed by employing ynamides as novel coupling reagents under extremely mild reaction conditions. The ynamides not only are effective for simple amide and dipeptide synthesis but can also be used for peptide segment condensation. Importantly, no racemization was detected during the activation of chiral carboxylic acids. Excellent amidation selectivity toward amino groups in the presence of -OH, -SH, -CONH, ArNH, and the NH of indole was observed, making the protection of these functional groups unnecessary in amide and peptide synthesis.

Exploration of the full potential of thioamide substitution as a tool in the chemical biology of peptides and proteins has been hampered by insufficient synthetic strategies for the site‐specific introduction of a thioamide bond into a peptide backbone. A novel ynamide‐mediated two‐step strategy for thiopeptide bond formation with readily available monothiocarboxylic acids as thioacyl donors is described. The α‐thioacyloxyenamide intermediates formed from the ynamides and monothiocarboxylic acids can be purified, characterized, and stored. The balance between their activity and stability enables them to act as effective thioacylating reagents to afford thiopeptide bonds under mild reaction conditions. Amino acid functional groups such as OH, CONH2, and indole NH groups need not be protected during thiopeptide synthesis. The modular nature of this strategy enables the site‐specific incorporation of a thioamide bond into peptide backbones in both solution and the solid phase.

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High cross-taxon congruence in species diversity patterns is essential for the use of surrogate taxa in biodiversity conservation, but presence and strength of congruence in species turnover patterns, and the relative contributions of abiotic environmental factors and biotic interaction towards this congruence, remain poorly understood. In our study, we used variation partitioning in multiple regressions to quantify cross-taxon congruence in community dissimilarities of vascular plants, geometrid and arciinid moths and carabid beetles, subsequently investigating their respective underpinning by abiotic factors and biotic interactions. Significant cross-taxon congruence observed across all taxon pairs was linked to their similar responses towards elevation change. Changes in the vegetation composition were closely linked to carabid turnover, with vegetation structure and associated microclimatic conditions proposed causes of this link. In contrast, moth assemblages appeared to be dominated by generalist species whose turnover was weakly associated with vegetation changes. Overall, abiotic factors exerted a stronger influence on cross-taxon congruence across our study sites than biotic interactions. The weak congruence in turnover observed particularly between plants and moths highlights the importance of multi-taxon approaches based on groupings of taxa with similar turnovers, rather than the use of single surrogate taxa or environmental proxies, in biodiversity assessments.

Abstract. 1. In the intensively cultivated major crop production areas of China, large knowledge gaps still prevail with regard to the current status of biodiversity in general, and especially in relation to agriculture management and planting patterns. Effective measures for species conservation are hence widely lacking.2. The diversity of ground beetle (Coleoptera: Carabidae) assemblages was compared between intensively managed wheat ⁄ maize fields, cotton monocultures, lawns, orchards and semi-natural woodland located in Quzhou county, a typical, intensively managed agricultural region in the North China Plain.3. Although significant differences were found in species composition between different habitats, diversity of ground beetles in non-cropping sites was not significantly higher than in intensively managed wheat ⁄ maize double-cropping fields, while cotton monocultures had a significant lower carabid diversity. A combination of intensively managed wheat ⁄ maize double-cropping fields with orchards appears to preserve substantial proportions of ground beetle diversity.4. To conserve the full spectrum of beetle species currently observed in the agricultural landscape of the North China Plain, the creation of both diverse habitats and a diversity of cropping systems are important, which includes a strengthening of less intensive farming practices.