The structure of a new pancreatic lipase inhibitor, lipstatin, produced by Streptomyces toxytridni was determined as (25, 35, 55,7Z, 1 0Z )-5-[(5' )-2-formamido-4-methylpentanoyloxy]-2-hexyl-3-hydroxy-7,10-hexadecadienoic lactone by spectroscopic and chemical methods.Structurally lipstatin is closely related to the knownesterase inhibitor esterastin. It contains a iV-formyl-L-leucine side chain instead of the iV-acetyl-L-asparagine in esterastin.

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Benzodiazepine-binding inhibitory (BBI) activity was detected in aqueous extracts of brain and peripheral tissues of rats. The BBI activity in brain and in adrenals was, at least partially, due to the presence of N-desmethyldiazepam and diazepam as shown by HPLC, UV-spectroscopy and mass spectrometry. In addition, BBI activity was found in standardized rat food, as well as in a variety of cereals and in other nutritive plant products. In wheat grains diazepam and N-desmethyldiazepam could be identified by HPLC and analysis by gas chromatography combined with mass spectrometry. The estimated amounts of the two benzodiazepines present in rat brain and adrenals and in wheat grains were in the low ppb range. Since laboratory contamination was rigorously excluded we conclude that diazepam and N-desmethyldiazepam are naturally occurring compounds. These findings may explain their occurrence in the brain and adrenals of animals.

Recently, several efficient supervisor synthesis approaches for distributed discrete event systems (DES) have been established. In this paper, the implementation of such supervisors on interacting distributed programmable logic controllers (PLCs) on a network is considered for the hierarchical and decentralized control approach elaborated in our previous work. A communication model that captures the controller behavior relevant for communication is developed, and a network architecture together with a scheduling policy that ensures correct operation of the networked controllers is proposed. In addition to the formal statements, simulation results for an example system are presented.