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ABSTRACT MotivationFreshwater ecosystems have been heavily impacted by land‐use changes, but data syntheses on these impacts are still limited. Here, we compiled a global database encompassing 241 studies with species abundance data (from multiple biological groups and geographic locations) across sites with different land‐use categories. This compilation will be useful for addressing questions regarding land‐use change and its impact on freshwater biodiversity. Main Types of Variables ContainedThe database includes metadata of each study, sites location, sample methods, sample time, land‐use category and abundance of each taxon. Spatial Location and GrainThe database contains data from across the globe, with 85% of the sites having well‐defined geographical coordinates. Major Taxa and Level of MeasurementThe database covers all major freshwater biological groups including algae, macrophytes, zooplankton, macroinvertebrates, fish and amphibians.
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Total synthesis of micrococcin P1 and thiocillin I enabled by Mo( vi ) catalyst
Thiopeptides are a class of potent antibiotics with promising therapeutic potential. We developed a novel Mo( vi )-oxide/picolinic acid catalyst for the cyclodehydration of cysteine peptides to form thiazoline heterocycles. With this powerful tool in hand, we completed the total syntheses of two representative thiopeptide antibiotics: micrococcin P1 and thiocillin I. These two concise syntheses (15 steps, longest linear sequence) feature a C–H activation strategy to install the trisubstituted pyridine core and thiazole groups. The synthetic material displays promising antimicrobial properties measured against a series of Gram-positive bacteria.
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- Award ID(s):
- 1753225
- PAR ID:
- 10089486
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 10
- Issue:
- 7
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 1971 to 1975
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c8sc04885a
