17 research outputs found
The creation and characterisation of a National Compound Collection: the Royal Society of Chemistry pilot
We present a summary of the National Compound Collection (NCC) pilot; which harvested chemical structure data from 746 publicly-available PhD theses to create an enhanced database of diverse and interesting (largely organic) molecular entities. The database comprised ∼75 000 structure entries, of which 70% were new to ChemSpider at the time of upload. The dataset was evaluated for structural uniqueness by twelve external drug discovery groups from the pharmaceutical, biotech, academic and not-for-profit sectors. These partners generated data reported here comparing the NCC pilot with their in-house compound collections. The proportion of NCC structures considered to be useful for drug discovery ranged from 5–80% depending on the strictness of the filters used; most interestingly from a drug discovery standpoint ∼13k NCC compounds (18% of the NCC) passed the filters and were of good diversity. These compounds are quite different from those that are already present in the screening collections but not so different that they are no longer considered to be drug-like. In general, the drug discovery teams would consider these compounds to be high value molecules for inclusion in their screening collections. This pilot addressed the potential value of unpublished data and explored the practicalities of large-scale data extraction, to inform both retrospective and prospective extraction of chemical data from theses
Diversification of ortho-fused cycloocta-2,5-dien-1-one cores and 8 to 6-Ring conversion by sigma bond C-C cleavage
Sequential treatment of 2-C6H4Br(CHO) with LiC≡CR1 (R1 = SiMe3, tBu), nBuLi, CuBr∙SMe2 and HC≡CCHClR2 [R2 = Ph, 4-CF3Ph, 3-CNPh, 4-(MeO2C)Ph] at -50 oC leads to formation of an intermediate carbanion (Z)-1,2-C6H4{CA(=O)C≡CBR1}{CH=CH(CH–)R2} (4). Low temperatures (-50 oC) favour attack at CB leading to kinetic formation of 6,8-bicycles containing non-classical C-carbanion enolates (5). Higher temperatures ( 10 oC to ambient) and electron deficient R2 favour retro σ-bond C-C cleavage regenerating 4 which subsequently closes on CA providing 6,6-bicyclic alkoxides (6). Computational modelling (CBS-QB3) indicates both pathways are viable and of similar energies. Reaction of 6 with H+ affords 1,2-dihydronaphthalen-1-ols, or under dehydrating conditions, 2-aryl-1-alkynylnaphthlenes. Enolates 5 react in situ with: H2O, D2O, I2, allylbromide, S2Me2, CO2 and lead to the expected C-E derivatives (E = H, D, I, allyl, SMe, CO2H) in 49-64% yield directly from intermediate 5. The parents (E = H; R1 = SiMe3, tBu; R2 = Ph) are versatile starting materials for NaBH4 and Grignard C=O additions, desilylation (when R1 = SiMe) and oxime formation. The latter allows formation of 6,9-bicyclics via Beckmann rearrangement. The 6,8-ring iodides are suitable Suzuki precursors for Pd-catalysed C-C coupling (81-87%); while the carboxylic acids readily form amides under T3P® conditions (71-95%)
Thermal Tolerance of the Coffee Berry Borer Hypothenemus hampei: Predictions of Climate Change Impact on a Tropical Insect Pest
Coffee is predicted to be severely affected by climate change. We determined the thermal tolerance of the coffee berry borer , Hypothenemus hampei, the most devastating pest of coffee worldwide, and make inferences on the possible effects of climate change using climatic data from Colombia, Kenya, Tanzania, and Ethiopia. For this, the effect of eight temperature regimes (15, 20, 23, 25, 27, 30, 33 and 35°C) on the bionomics of H. hampei was studied. Successful egg to adult development occurred between 20–30°C. Using linear regression and a modified Logan model, the lower and upper thresholds for development were estimated at 14.9 and 32°C, respectively. In Kenya and Colombia, the number of pest generations per year was considerably and positively correlated with the warming tolerance. Analysing 32 years of climatic data from Jimma (Ethiopia) revealed that before 1984 it was too cold for H. hampei to complete even one generation per year, but thereafter, because of rising temperatures in the area, 1–2 generations per year/coffee season could be completed. Calculated data on warming tolerance and thermal safety margins of H. hampei for the three East African locations showed considerably high variability compared to the Colombian site. The model indicates that for every 1°C rise in thermal optimum (Topt.), the maximum intrinsic rate of increase (rmax) will increase by an average of 8.5%. The effects of climate change on the further range of H. hampei distribution and possible adaption strategies are discussed. Abstracts in Spanish and French are provided as supplementary material Abstract S1 and Abstract S2
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Structure-activity relationships of the antimalarial agent artemisinin. 7. Direct modification of (+)-artemisinin and in vivo antimalarial screening of new, potential preclinical antimalarial candidates
Structure−Activity Relationships of the Antimalarial Agent Artemisinin. 7. Direct Modification of (+)-Artemisinin and In Vivo Antimalarial Screening of New, Potential Preclinical Antimalarial Candidates
New innovation models in pharmaceutical R&D
The efficiency of pharmaceutical research and development (R&D) reflected by increasing costs of R&D, long timelines, and low probabilities of technical and regulatory success decreased continuously in the past years. Today, the costs for discovering and developing a new drug are enormously high with more than USD 2 billion per new molecular entity (NME), while the average overall success of a research project to provide an NME is in the single-digit percentage rate, and the total timelines of R&D easily exceeds 10 years questioning the return on investment (ROI) of pharmaceutical R&D. As a consequence and also caused by numerous patent expirations of blockbuster drugs that increased the pressure to return to an acceptable ROI, the pharmaceutical industry addressed this challenge and the related causes and identified several actions that need to be taken to increase the output/input ratio of R&D. This book chapter will review the pipeline sizes and the R&D investments of multinational pharmaceutical companies, will describe new processes that have been implemented to increase the reach and to reduce costs of pharmaceutical R&D, and it will illustrate new innovation models that were developed to increase the R&D efficiency
Synthesis of Fluorinated and Nonfluorinated Tebufenpyrad Analogues for the Study of Anti-angiogenesis MOA
In this contribution we report the
synthesis of fluorinated and
nonfluorinated tebufenpyrad analogues to explore potential druglike
properties through the phenotypic screening as part of the Lilly Open
Innovation Drug Discovery (OIDD) program