Abstract. Reconstructions of global hydroclimate during the Common Era (CE; the past ∼2000 years) are important for providing context for current and future global environmental change. Stable isotope ratios in water are quantitative indicators of hydroclimate on regional to global scales, and these signals are encoded in a wide range of natural geologic archives. Here we present the Iso2k database, a global compilation of previously published datasets from a variety of natural archives that record the stable oxygen (δ18O) or hydrogen (δ2H) isotopic compositions of environmental waters, which reflect hydroclimate changes over the CE. The Iso2k database contains 759 isotope records from the terrestrial and marinemore »
Enantioselective construction of the tricyclic core of curcusones A–D via a cross-electrophile coupling approach
Herein we report our recent progress toward the enantioselective total synthesis of the diterpenoid natural products curcusones A–D by means of complementary Stetter annulation or ring-closing metathesis (RCM) disconnections. Using the latter approach, we have achieved the concise construction of the 5–7–6 carbocyclic core embedded in each member of the curcusone family. Essential to this route is the use of a cross-electrophile coupling strategy, which has not previously been harnessed in the context of natural product synthesis.
- Award ID(s):
- 1800511
- Publication Date:
- NSF-PAR ID:
- 10146309
- Journal Name:
- Chemical Science
- Volume:
- 10
- Issue:
- 45
- Page Range or eLocation-ID:
- 10562 to 10565
- ISSN:
- 2041-6520
- Sponsoring Org:
- National Science Foundation
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