The dehydration of N-acetylglucosamine (GlcNAc) to enantiopure dihydroxyethyl acetamidofuran (Di-HAF)

The first multi-gram synthesis of enantiopure dihydroxyethyl acetamidofuran (Di-HAF) is reported. Under optimized conditions, GlcNAc dehydrates in pyridine in the presence of phenylboronic acid and triflic acid to afford Di-HAF in 73% yield and 99.3% ee in just 30 minutes. This protocol opens the door for further research on this bio-renewable building block which is now available as a chiral pool synthon. A plausible mechanism of its formation and of the subsequent dehydration of Di-HAF into well-known 3-acetamido-5-acetylfuran (3A5AF) is proposed.</p

Correction: π-Facial selectivity in the Diels–Alder reaction of glucosamine-based chiral furans and maleimides

Correction for 'π-Facial selectivity in the Diels-Alder reaction of glucosamine-based chiral furans and maleimides' by Cornelis H. M. van der Loo et al., Org. Biomol. Chem., 2023, 21, 1888-1894, https://doi.org/10.1039/D2OB02221D. </p

Correction: π-Facial selectivity in the Diels–Alder reaction of glucosamine-based chiral furans and maleimides

Correction for 'π-Facial selectivity in the Diels-Alder reaction of glucosamine-based chiral furans and maleimides' by Cornelis H. M. van der Loo et al., Org. Biomol. Chem., 2023, 21, 1888-1894, https://doi.org/10.1039/D2OB02221D. </p

Photodissociation of the OD radical at 226 and 243 nm

The photodissociation dynamics of state selected OD radicals has been examined at 243 and 226 nm using velocity map imaging to probe the angle–speed distributions of theD(2S) and O(3P2) products. Both experiment and complementary first principle calculations demonstrate that photodissociation occurs by promotion of OD from high vibrational levels of the ground X 2Π state to the repulsive 1 2Σ− state

Correction: π-Facial selectivity in the Diels–Alder reaction of glucosamine-based chiral furans and maleimides

Correction for 'π-Facial selectivity in the Diels-Alder reaction of glucosamine-based chiral furans and maleimides' by Cornelis H. M. van der Loo et al., Org. Biomol. Chem., 2023, 21, 1888-1894, https://doi.org/10.1039/D2OB02221D. </p

Correction: π-Facial selectivity in the Diels–Alder reaction of glucosamine-based chiral furans and maleimides

Correction for 'π-Facial selectivity in the Diels-Alder reaction of glucosamine-based chiral furans and maleimides' by Cornelis H. M. van der Loo et al., Org. Biomol. Chem., 2023, 21, 1888-1894, https://doi.org/10.1039/D2OB02221D. </p

Intermediate stable states in substance use

Many people across the world use potentially addictive legal and illegal substances, but evidence suggests that not all use leads to heavy use and dependence, as some substances are used moderately for long periods of time. Here, we empirically examine, the stability of and transitions between three substance use states: zero-use, moderate use, and heavy use. We investigate two large datasets from the US and the Netherlands on yearly usage and change of alcohol, nicotine, and cannabis. Results, which we make available through an extensive interactive tool, suggests that there are stable moderate use states, even after meeting criteria for a positive diagnosis of substance abuse or dependency, for both alcohol and cannabis use. Moderate use of tobacco, however, was rare. We discuss implications of recognizing three states rather than two states as a modeling target, in which the moderate use state can both act as an intervention target or as a gateway between zero use and heavy use