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Abstract PHPT1 is a protein histidine phosphatase that has been implicated in several disease pathways, but the chemical tools necessary to study the biological roles of this enzyme and investigate its utility as a therapeutic target have yet to be developed. To this end, the discovery of PHPT1 inhibitors is an area of significant interest. Here, we report an investigation of illudalic acid and illudalic acid analog‐based inhibition of PHPT1 activity. Four of the seven analogs investigated had IC₅₀values below 5 μM, with the most potent compound (IA1‐8H2) exhibiting an IC₅₀value of 3.4±0.7 μM. Interestingly, these compounds appear to be non‐covalent, non‐competitive inhibitors of PHPT1 activity, in contrast to other recently reported PHPT1 inhibitors. Mutating the three cysteine residues to alanine has no effect on inhibition, indicating that cysteine is not critical for interactions between inhibitor and enzyme. 

Abstract The coordinated, cooperative use of microwave heating with conventional heating can provide advantages in chemical synthesis. Here, heterogeneous mixtures comprising ionic, highly microwave‐absorbing organic reagents and nearly microwave‐transparent arene solvents are heated conventionally and/or with microwaves, resulting in faster and, in some cases, higher yielding reactions when the two heating methods are applied cooperatively as compared to either method independently. Control experiments in more polar arene solvents show no advantage of cooperative heating, consistent with selective microwave heating phenomena. The experiments are facilitated by reactor technology that regulates internal reaction temperature and coordinates the application of conventional and microwave heating. The positive outcomes in this initial exploratory system suggest that cooperative heating can offer benefits in other systems designed for selective microwave heating. 

Abstract Microwave (MW) heating is more effective than conventional (CONV) heating for promoting a high‐temperature oxidative cycloisomerization reaction that was previously reported as a key step in a total synthesis of the natural product illudinine. The thermal reaction pathway as envisioned is an inverse electron‐demand dehydro‐Diels–Alder reaction with in situ oxidation to generate a substituted isoquinoline, which itself is unstable to the reaction conditions. Observed reaction yields were higher at a measured bulk temperature of 200 °C than at 180 °C or 220 °C; at 24 hours than at earlier or later time points; and when the reaction solution was heated using MW energy as opposed to CONV heating with a metal heat block. Selective MW heating of polar solute aggregates is postulated to explain these observations.