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In 2001, our curiosity to understand the stereochemistry of C−H metalation with Pd prompted our first studies in Pd(II)‐catalyzed asymmetric C−H activation (RSC Research appointment: 020 7451 2545, Grant: RG 36873, Dec. 2002). We identified four central challenges: 1. poor reactivity of simple Pd salts with native substrates; 2. few strategies to control site selectivity for remote C−H bonds; 3. the lack of chiral catalysts to achieve enantioselectivity via asymmetric C−H metalation, and 4. low practicality due to limited coupling partner scope and the use of specialized oxidants. These challenges necessitated new strategies in catalyst and reaction development. For reactivity, we developed approaches to enhance substrate–catalyst affinity together with novel bifunctional ligands which participate in and accelerate the C−H cleavage step. For site‐selectivity, we introduced the concept of systematically modulating the distance and geometry between a directing template, catalyst, and substrate to selectively access remote C−H bonds. For enantioselectivity, we devised predictable stereomodels for catalyst‐controlled enantioselective C−H activation based on the participation of bifunctional ligands. Finally, for practicality, we have developed varied catalytic manifolds for Pd(II) to accommodate diverse coupling partners while employing practical oxidants such as simple peroxides. These advances have culminated in numerous C−H activation reactions, setting the stage for broad industrial applications. [ABSTRACT FROM AUTHOR]

Remote C−H functionalization of heterocyclic biaryls will be of great importance in synthesis and medicinal chemistry. Through adjusting the geometric relationship of the directing atom and target C−H bonds, two new catalytic templates have been developed to enable the functionalization of the more hindered ortho‐C−H bonds of heterobiaryls bearing directing heteroatom at the meta‐ or para‐positions, affording unprecedented site‐selectivity. The use of template chaperone also overcomes product inhibition and renders the directing templates catalytic. The utility of this protocol was demonstrated by olefination of heterocyclic biaryls with various substituents, overriding conventional steric and electronic effects. These ortho‐C−H olefinated heterobiaryls are sterically hindered and can often be challenging to prepare through aryl‐aryl coupling reactions. [ABSTRACT FROM AUTHOR]

The development of C(sp3)−H functionalization reactions that use common protecting groups and practical oxidants remains a significant challenge. Herein we report a monoprotected aminoethyl thioether (MPAThio) ligand‐enabled β‐C(sp3)−H lactamization of tosyl‐protected aliphatic amides using tert‐butyl hydrogen peroxide (TBHP) as the sole oxidant. This protocol features exceedingly mild reaction conditions, reliable scalability, and the use of practical oxidants and protecting groups. Further derivatization of the β‐lactam products enables the synthesis of a range of biologically important motifs including β‐amino acids, γ‐amino alcohols, and azetidines. [ABSTRACT FROM AUTHOR]

Cross-coupling between two similar or identical functional groups to form a new C–C bond is a powerful tool to rapidly assemble complex molecules from readily available building units, as seen with olefin cross-metathesis or various types of cross-electrophile coupling1,2. The Kolbe electrolysis involves the oxidative electrochemical decarboxylation of alkyl carboxylic acids to their corresponding radical species followed by recombination to generate a new C–C bond3–12. As one of the oldest known Csp3–Csp3 bond-forming reactions, it holds incredible promise for organic synthesis, yet its use has been almost non-existent. From the perspective of synthesis design, this transformation could allow one to agnostically execute syntheses without regard to polarity or neighbouring functionality just by coupling ubiquitous carboxylates13. In practice, this promise is undermined by the strongly oxidative electrolytic protocol used traditionally since the nineteenth century5, thereby severely limiting its scope. Here, we show how a mildly reductive Ni-electrocatalytic system can couple two different carboxylates by means of in situ generated redox-active esters, termed doubly decarboxylative cross-coupling. This operationally simple method can be used to heterocouple primary, secondary and even certain tertiary redox-active esters, thereby opening up a powerful new approach for synthesis. The reaction, which cannot be mimicked using stoichiometric metal reductants or photochemical conditions, tolerates a range of functional groups, is scalable and is used for the synthesis of 32 known compounds, reducing overall step counts by 73%.An Ni-electrocatalytic system can couple two different carboxylates using doubly decarboxylative cross-coupling, tolerating a range of functional groups, being scalable, used for the synthesis of 32 known compounds and reducing overall step counts by 73%. [ABSTRACT FROM AUTHOR]

Fluorine is known to promote ortho‐C−H metalation. Based upon this reactivity, we employed an activated norbornene that traps the ortho‐palladation intermediate and is then relayed to the meta position, leading to meta‐selective C−H arylation of fluoroarenes. Deuterium experiment suggests that this meta‐arylation is initiated by ortho C−H activation and the catalytic cycle is terminated by C‐2 protonation. A dual‐ligand system is crucial for the observed high reactivity and site selectivity. Applying this approach to simple benzene or other arenes also affords arylation products with good yield and site selectivity. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Display omitted] Elevated levels of receptor tyrosine kinase-like orphan receptor 1 (RORl) expression are observed in multiple hematological and solid tumors, but not in most of the healthy adult tissues, identifying ROR1 as an attractive target for tumor-specific therapy. Herein we will describe the discovery of macrocyclic peptides as binders of the extracellular Cysteine-Rich Domain (CRD) of human ROR1 via mRNA in vitro selection technology using the PDPS platform, followed by exploration of sidechain SAR of parent macrocycle peptides, fluorescently labeled analogs, and a Peptide Drug Conjugate (PDC). The parent macrocyclic peptides represented by Compound 1 and Compound 14 displayed nanomolar cell-based binding to ROR1 and relatively good internalization in 786-O and MDA-MB-231 tumor cell lines. However, these peptides were not observed to induce apoptosis in Mia PaCa-2 cells, a model pancreatic tumor cell line with a relatively low level of cell surface expression of ROR1. [ABSTRACT FROM AUTHOR]

A general β‐C−H arylation of electron‐deficient thiophenes, pyrroles, and furans has been developed using ligand‐modulated palladium catalyst. The use of a modified norbornene is crucial for reversing the conventional α‐selectivity of these substrates. This method features good yields, high β‐selectivity, and good tolerance of functional groups. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The palladium(II)-catalyzed C(sp3)−H alkynylation of oligopeptides was developed with tetrabutylammonium acetate as a key additive. Through molecular design, the acetylene motif served as a linchpin to introduce a broad range of carbonyl-containing pharmacophores onto oligopeptides, thus providing a chemical tool for the synthesis and modification of novel oligopeptide-pharmacophore conjugates by C−H functionalization. Dipeptide conjugates with coprostanol and estradiol were synthesized by this method for potential application in targeted drug delivery to tumor cells with overexpressed nuclear hormone receptors. [ABSTRACT FROM AUTHOR]

A method for the decarboxylative macrocyclization of peptides bearing N-terminal Michael acceptors has been developed. This synthetic method enables the efficient synthesis of cyclic peptides containing γ-amino acids and is tolerant of functionalities present in both natural and non-proteinogenic amino acids. Linear precursors ranging from 3 to 15 amino acids cyclize effectively under this photoredox method. To demonstrate the preparative utility of this method in the context of bioactive molecules, we synthesized COR-005, a somatostatin analogue that is currently in clinical trials. [ABSTRACT FROM AUTHOR]

A one-step synthesis of Fmoc-protected aryl/heteroaryl-substituted phenylalanines (Bip derivatives) using the nonaqueous palladium-catalyzed Suzuki-Miyaura cross-coupling (SMC) reaction of Fmoc-protected bromo- or iodophenylalanines is reported. This protocol allows for the direct formation of a variety of unnatural biaryl-containing amino acids in good to excellent yield, which can be readily used in subsequent Fmoc solid-phase peptide synthesis. The synthetic utility of this method is also demonstrated by the SMC reaction of bromophenylalanine-containing tripeptides. [ABSTRACT FROM AUTHOR]

In an effort to identify a potential back-up to apixaban (Eliquis®), we explored a series of diversified P4 moieties. Several analogs with substituted gem-dimethyl moieties replacing the terminal lactam of apixaban were identified which demonstrated potent FXa binding affinity (FXa K i ), good human plasma anticoagulant activity (PT EC 2x ), cell permeability, and oral bioavailability. [ABSTRACT FROM AUTHOR]

Abstract: Blockade of the P2Y1 receptor is important to the treatment of thrombosis with potentially improved safety margins compared with P2Y12 receptor antagonists. Investigation of a series of urea surrogates of the diaryl urea lead 3 led to the discovery of 2-amino-1,3,4-thiadiazoles in the 7-hydroxy-N-neopentyl spiropiperidine indolinyl series as potent P2Y1 receptor antagonists, among which compound 5a was the most potent and the first non-urea analog with platelet aggregation (PA) IC50 less than 0.5μM with 10μM ADP. Several 2-amino-1,3,4-thiadiazole analogs such as 5b and 5f had a more favorable pharmacokinetic profile, such as higher C trough, lower Cl, smaller V dss, and similar bioavailability compared with 3. [Copyright &y& Elsevier]

Preclinicalantithrombotic efficacy and bleeding models have demonstratedthat P2Y1antagonists are efficacious as antiplatelet agentsand may offer a safety advantage over P2Y12antagonistsin terms of reduced bleeding liabilities. In this article, we describethe structural modification of the tert-butyl phenoxyportion of lead compound 1and the subsequent discoveryof a novel series of conformationally constrained ortho-anilino diaryl ureas. In particular, spiropiperidine indoline-substituteddiaryl ureas are described as potent, orally bioavailable small-moleculeP2Y1antagonists with improved activity in functional assaysand improved oral bioavailability in rats. Homology modeling and ratPK/PD studies on benchmark compound 3lwill also be presented.Compound 3lwas our first P2Y1antagonistto demonstrate a robust oral antithrombotic effect with mild bleedingliability in the rat thrombosis and hemostasis models. [ABSTRACT FROM AUTHOR]

Abstract: Preclinical data suggests that P2Y1 antagonists, such as diarylurea compound 1, may provide antithrombotic efficacy similar to P2Y12 antagonists and may have the potential of providing reduced bleeding liabilities. This manuscript describes a series of diarylureas bearing solublizing amine side chains as potent P2Y1 antagonists. Among them, compounds 2l and 3h had improved aqueous solubility and maintained antiplatelet activity compared with compound 1. Compound 2l was moderately efficacious in both rat and rabbit thrombosis models and had a moderate prolongation of bleeding time in rats similar to that of compound 1. [Copyright &y& Elsevier]

The discovery of the copper-promoted Chan-Lam coupling reaction with boronic acids more than ten years ago has greatly advanced the carbon-heteroatom cross-coupling chemistry. The N-arylation/O-arylation methodology is now a powerful new synthetic tool, made even more attractive by the mild conditions required. Significant progress has been made in expanding the scope and the applications as well as understanding the mechanism of this reaction. This review includes an examination of various C-X cross-couplings using boronic acids and their derivatives, and a survey of the mechanistic studies that have been carried out. [ABSTRACT FROM AUTHOR]

An effective microwave-assisted urea formation from cyclopentyl- or isopropyl-substituted ureas is described. This novel transamidation methodology provided ureas IIa – IIq in good yields via microwave irradiation of the cyclopentyl- or isopropyl-substituted ureas with excess (5–10 equiv) of amines at 150 °C in THF/DMSO. [ABSTRACT FROM AUTHOR]

An efficient synthesis of monofluorophenols via the �reaction of difluorobenzene derivatives with potassium trimethyl�silanoate in moderate to excellent yields is described. High regio�selectivity was observed in some cases. [ABSTRACT FROM AUTHOR]

Abstract: We previously disclosed a series of highly potent FXa inhibitors bearing α-substituted (CH2NR1R2) phenylcyclopropyl P4 moieties in the pyrazolodihydropyridone core system. Herein, we describe our continuous SAR efforts in this series. Effects of the C-3 substitution of the pyrazolodihydropyridone core and the α-substitution (R group) of the cyclopropyl ring on FXa binding affinity (FXa K i), human plasma anticoagulant activity (PT EC2×) and permeability are discussed. A set of compounds obtained from optimization of the R group and the C-3 substituent were orally bioavailable in dogs. Furthermore, representative compounds were highly efficacious in the rabbit arterio-venous shunt thrombosis model (EC50s=29–81nM). [Copyright &y& Elsevier]

Abstract: Ortho-substituted biphenyl moieties are widely used in drug design. We herein report a successful use of the perpendicular conformation of the alpha-substituted phenylcyclopropyl groups to mimic the aplanar, biologically active conformation of the ortho-substituted biphenyl moieties to achieve structural diversity. This is exemplified by the design and synthesis of a series of highly potent pyrazole bicyclic-based Factor Xa (FXa) inhibitors bearing alpha-substituted phenylcyclopropyl P4 moieties. The designed perpendicular conformation was confirmed by the X-ray structure of FXa-bound compound 2r. The potential structural basis for the high FXa potency in the phenylcyclopropyl P4 analogs and their improved FXa inhibitory activities compared with the biphenyl P4 counterparts are discussed. [Copyright &y& Elsevier]