Disulfide-rich peptides (DRPs) are a class of peptides that are constrained through two or more disulfide bonds. Though natural DRPs have been extensively exploited for developing protein binders or potential therapeutics, their synthesis and re-engineering to bind new targets are not straightforward due to difficulties in handling the disulfide pairing problem. Rationally designed DRPs with an intrinsically orthogonal disulfide pairing propensity provide an alternative to the natural scaffolds for developing functional DRPs. Herein we report the use of tandem CXPen/PenXC motifs ((C) cysteine; (Pen) penicillamine; (X) any residue) for directing the oxidative folding of peptides. Diverse tricyclic peptides were designed and synthesized by varying the pattern of C/Pen residues and incorporating a tandem CXPen/PenXC motif into peptides. The folding of these peptides was determined primarily by C/Pen patterns and tolerated to sequence manipulations. The applicability of the designed C/Pen-DRPs was demonstrated by designing protein binders using an epitope grafting strategy. This study thus demonstrates the potential of using orthogonal disulfide pairing to design DRP scaffolds with new structures and functions, which would greatly benefit the development of multicyclic peptide ligands and therapeutics.The high demand for new and efficient routes toward synthesis of nitrogen-containing heterocyclic scaffolds has inspired organic chemists to discover several methodologies over recent years. This Perspective highlights one standout approach, which involves the use of pyridotriazoles and related compounds in denitrogenative transformations. Readily available pyridotriazoles undergo ring-chain isomerization to produce uniquely reactive α-diazoimines. Such reactivity, enabled by metal catalysts, additives, or visible-light irradiation, can be applied in transannulation, insertion, cyclopropanation, and many other transformations.A convergent synthetic route to the fungal metabolites cladosins B and C has been developed, affording these natural products in 29% and 27% overall yield, respectively. The cladosins are rare examples of hybrid polyketides featuring a 3-enamine tetramic acid group derived from l-valine. Key steps in this modular six-step sequence include a DMAP-mediated O- to C-acyl rearrangement to unite the side chains with the tetramic acid core and subsequent amine incorporation using either ammonium acetate or HMDS.This report describes the first example of palladium-catalyzed ortho-C-H glycosylation/ipso-alkenylation of aryl iodides, and the easily accessible glycosyl chlorides are used as a glycosylation reagent. The reaction is compatible with the functional groups of the substrates, and a series of C-aryl glycosides have been synthesized in good to excellent yield and with excellent diastereoselectivity. https://www.selleckchem.com/products/r-hts-3.html It is found that a cheap 5-norbornene-2-carbonitrile as a transient mediator can effectively promote this reaction. In addition, ipso-arylation and cyanation were also realized by the strategy.Three new dimeric bis-guanidinate zinc(II) alkyl, halide, and hydride complexes [LZnEt] 2 (1), [LZnI] 2 (2) and [LZnH] 2 (3) were prepared. Compound 3 was successfully employed for the hydrosilylation and hydroboration of a vast number of ketones. The catalytic performance of 3 in the hydroboration of acetophenone exhibits a turnover frequency, reaching up to 5800 h-1, outperforming that of reported zinc hydride catalysts. Notably, both intra- and intermolecular chemoselective hydrosilylation and hydroboration reactions have been investigated.Cyclic anhydrides are versatile synthons and functional comonomers. Herein, we reported an organic base-promoted carboxylative cyclization of 2-butenoates with carbon dioxide to produce important glutaconic anhydrides in good yields. This metal-free reaction showed broad substrate scopes and proceeded under mild reaction conditions.A modular tandem synthesis of 2-carboxybenzofurans from 2-gem-dibromovinylphenols has been established based on a sequence of Cu-catalyzed intramolecular C-O coupling and Mo(CO)6-mediated intermolecular carbonylation reactions. This protocol allowed one-step access to a broad variety of functionalized benzofuran-2-carboxylic acids, esters, and amides in good to excellent yields under Pd- and CO gas-free conditions.A simple chiral primary-tertiary diamine derived from C2-symmetric 1,2-diphenylethane-1,2-diamine as the organocatalyst in combination with the trifluoroacetic acid additive for the asymmetric Mannich reaction of cyclic N-sulfonyl trifluoromethylated ketimines and methyl ketones afforded the desired product with high enantioselectivity (73-96% ee). The reactions proceeded well for a variety of different substituted cyclic N-sulfonyl trifluoromethyl ketimines and various alkyl methyl ketones, providing access to diverse enantioenriched benzo-fused cyclic sulfamidate N-heterocycles bearing a trifluoromethylated α-tetrasubstituted carbon stereocenter. This study also investigated the diastereoselective reduction of the carbonyl group and ring cleavage reduction of the sulfamidate group of the corresponding Mannich product.A tandem synthesis of quinazolinones from 2-aminobenzonitriles is demonstrated here by using an aliphatic alcohol-water system. For this transformation, a cheap and easily available cobalt salt and P(CH2CH2PPh2)3 (PP3) ligand were employed. The substrate scope, scalability, and synthesis of natural products exhibited the vitality of this protocol.By turning on or switching off the directing effect of the C3-OH-located o-diphenylphosphanylbenzoyl (o-DPPB) group in glycals, a reagent-controlled protocol for divergent and regio- and stereoselective syntheses of C-glycosides has been established. In particular, the silence of the directing effect of o-DPPB was achieved by the introduction of a ZnCl2 additive, which is operationally simple and efficient. The flexibility of the novel protocol was exhibited not only by the easy access of both α- and β-C-glycosides but also by the versatility of the obtained formal Ferrier rearrangement products, which can be easily derivatized to various C-glycoside analogues owing to the embedded multifunctionalities.