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2,6-Lutidine has been identified as a beneficial additive for the oxidative cleavage of olefins to ketones by NaIO4 in the presence of catalytic RuCl3, improving the yield and shortening the reaction times. In the absence of 2,6-lutidine reactions stalled at the diol intermediate with incomplete conversion to the desired ketones. The reaction protocol described herein also avoids the use of harmful solvents such as CCl4 and DCE and is tolerant of a range of functional groups.

This industry update covers the period from 1 September through 30 September 2017, and is based on information sourced from company press releases, scientific literature, patents and various news websites. The month saw the US FDA approve three new molecular entities, Aliqopa (copanlisib dihydrochloride) (Bayer Healthcare); Solosec (secnidazole) (Symbiomix Therapeutics) and Verzenio (abemaciclib) (Eli Lilly and Co). Intarcia Therapeutics Inc. has its application for approval of a novel drug device combination of exenatide for the treatment of diabetes rejected by FDA but said that it will work to address the concerns and refile the application. The impact of biosimilars in the market is steadily increasing with seven biosimilars approved in the USA and Sandoz hoping to add to this with its announcement that FDA has accepted its Biologics License Application for a biosimilar version of Roche's Rituxan. Circassia announced positive top line results of a respiratory drug, Duaklir (for the treatment of chronic obstructive pulmonary disease) and Sarepta (for its new treatment for Duchenne muscular dystrophy). Axovant Sciences Ltd announced the failure if its drug Intepirdine in the treatment of Alzheimer's, adding to a growing list of drug failures in this area. There were a number of developments in the area of oncology with Bristol-Myers Squibb and Infinity Pharmaceuticals announcing an expansion of their collaboration looking at combination treatments, as well as Eli Lilly and Co's approval for Verzenio. Rani Therapeutics and Intra-Cellular Therapies announced successful funding rounds to support their drug programs. Allergan announced a novel licensing deal for its dry eye drug, Restasis, which it hopes would allow it to stave off patent challenges from several companies looking to develop generic versions of the drug. New research suggests that loss of sense of smell can be linked to an increased risk of developing Parkinson's disease.

Spleen Tyrosine Kinase (SYK) is a well-studied enzyme with therapeutic applications in oncology and autoimmune diseases. We identified an azabenzimidazole (ABI) series of SYK inhibitors by mining activity data of 86,000 compounds from legacy biochemical assays with SYK and other homologous kinases as target enzymes. A structure-based design and hybridization approach was then used to improve the potency and kinase selectivity of the hits. Lead compound 23 from this novel ABI series has a SYK IC50 = 0.21 nM in a biochemical assay and inhibits growth of SUDHL-4 cells at a GI50 = 210 nM.

A procedure for the formation of aryl amides through the palladium-catalyzed coupling of nitriles and aryl bromides, via the formation of intermediary silanoate derived imidate species is reported. Optimization was undertaken and examples of the process are described that furnish the products in up to 86% isolated yield.

We report a two step one-pot method for the synthesis of 2-bromo-6-aryl[5 H ]pyrrolo[2,3- b ]pyrazines. The process makes use of a cleaner copper-free Sonogashira coupling and an improved base-mediated 5- exo -dig cyclisation to afford the products in good yields. This method expands the scope to structures that are poorly represented in the literature and incorporates a halide for further synthetic elaboration.

The olefin cross-metathesis reaction allows rapid access to 1,5-dicarbonyl intermediates which, upon treatment with a primary or secondary amine, allow the synthesis of a range of multisubstituted carbocyclic aryl amines. This de novo arene synthesis yields nonclassical substitution patterns in a regioselective and predictable approach that is compatible with several functional groups.

Piperazines are found widely in commercially-available compounds and bioactive molecules (including many drugs). However, in the vast majority of these molecules, the piperazine ring is isolated (i.e. not fused to another ring) and is not substituted on any of its carbon atoms. A modular synthetic approach is described in which combinations of cyclic sulfamidate and hydroxy sulfonamide building blocks may be converted into piperazines and related 1,4-diazepine and 1,5-diazocane scaffolds. By variation of the combinations of building blocks used, it was possible to vary the ring size, substitution and configuration of the resulting heterocyclic scaffolds. The approach was exemplified in the synthesis of a range of heterocyclic scaffolds that, on decoration, would target lead-like chemical space. It was demonstrated that lead-like small molecules based on these scaffolds would likely complement those found in large compound collections.

Ring-opening of cyclic sulfamidates with propargylic sulfonamides yielded substrates for a gold-catalyzed cyclization to yield tetrahydropyrazines. Manipulation of the tetrahydropyrazines, by reduction or using multicomponent reactions, yielded piperazine scaffolds in which substitution of the carbon atoms was varied. Such scaffolds may have value in the synthesis of novel screening compounds with lead-like molecular properties.

We describe the development of a sustainable ester amidation process. Base and solvent screening, combined with the application of Design of Experiments methodology was employed to identify an optimized set of reaction conditions using a sustainable protocol. Utilizing these optimized conditions, treatment of a range of ester derivatives with amino alcohols in the presence of a catalytic quantity of potassium phosphate deploying iso-propanol as solvent results in the highly efficient generation of a range of amido-alcohol derivatives in good to excellent yield, accompanied with excellent reaction mass efficiency (RME).

The starting amide salts are prepared by reaction of appropriate nitriles with Tms—OK according to a known procedure.

The development of a novel palladium-catalysed amidation approach towards 5,7,8,9-tetrahydropyrimido[4,5- b ][1,4]diazepin-6-one templates is highlighted. The route proceeds through the reaction of an amino amide, generated by 1,4-addition of an amine to an acrylamide, with 5-bromo-2,4-dichloropyrimidine and final palladium-catalysed cyclisation to provide the functionalised scaffold in up to 60% isolated yield over three steps. The route offers efficiency advantages over the previously reported nitro-reduction cyclisation approach to these molecules. It also provides alternative means to introduce bulky alkyl substituents at the amide nitrogen. The application of this route in the synthesis of a variety of analogues is described.

A two-step synthesis of 3-(2-chloropyrimidin-4-yl)imidazo[1,2-a]pyridines is presented. The late stage elaboration of the imidazopyridine through a cyclocondensation allows a rapid access to a variety of substitution patterns. The intermediate enol ethers were obtained from inexpensive reagents in a ligand-free Heck coupling. This methodology has been extended to the formation of pyrazolo[1,5-a]pyridines via a formal 1,3-dipolar cycloaddition.

We report a two step one-pot method for the synthesis of 2-bromo-6-aryl[5 H ]pyrrolo[2,3- b ]pyrazines. The process makes use of a cleaner copper-free Sonogashira coupling and an improved base-mediated 5- exo -dig cyclisation to afford the products in good yields. This method expands the scope to structures that are poorly represented in the literature and incorporates a halide for further synthetic elaboration.

A catalytic amidation method has been developed, employing 2,2,2-trifluoroethanol to facilitate condensation of unactivated esters and amines, enabling the synthesis of a range of amide products in good to excellent yields. Mechanistic studies indicate the reaction proceeds through a trifluoroethanol-derived active ester intermediate.

BEMP is an efficient catalyst for reactions of amino alcohols with dimethyl carbonate and a variety of methyl esters.

Natural products (IX)-(XII) are synthesized from the common precursor (VIII), which requires the change of the general procedure to the use of ZnCl2 as a catalyst because the more vigorous acetic acidic method leads to the products in significantly lower yield.

[reaction: see text] The cycloaddition of N-phenyltriazolinedione to a pair of spirocyclic cycloheptatrienes featuring a tetrahydrofuran or tetrahydropyran ring is shown to proceed with opposite pi-facial stereoselectivity. In addition, the furan undergoes direct [4+2] cycloaddition to the cycloheptatriene whereas the pyran product is a diazetidine.

A new method for preparing naphthyl amines from 1,5 unsaturated dicarbonyl precursors is described; the utility of this new method was proven in the syntheses of several natural products, all containing the benzo[c]phenanthridine core and enabled by a radical promoted cyclisation of the naphthyl amine products formed in the key cyclisation.

Olefin metathesis of allylic alcohols (I) with methyl vinyl ketones (II) in the presence of Zhan-1B catalyst and subsequent Dess-Martin-periodinane oxidation produces generally not-assigned mixtures of unsaturated diones.

Ring-opening of cyclic sulfamidates with propargylic sulfonamides yielded substrates for a gold-catalyzed cyclization to yield tetrahydropyrazines. Manipulation of the tetrahydropyrazines, by reduction or using multicomponent reactions, yielded piperazine scaffolds in which substitution of the carbon atoms was varied. Such scaffolds may have value in the synthesis of novel screening compounds with lead-like molecular properties.

Directed ortho-lithiation is used to form [benzene-U-13C]-2-chlorobenzaldehyde, the key building block for preparation of labelled racemic Clopidogrel ([benzene-U-13C]-rac-SR25990C). Some practical observations are reported concerning the metalation of some derivatives of benzoic acid. Copyright © 2000 John Wiley & Sons, Ltd.