An asymmetric approach for the first total synthesis of (−)-rhodomollanol A, a highly oxidized diterpenoid, is described. The efficient synthetic strategy features three key transformations: (1) an oxidative dearomatization-induced (5 + 2) cycloaddition/pinacol-type 1,2-acyl migration cascade to build up the bicyclo­[3.2.1]­octane skeleton; (2) a retro-Dieckmann fragmentation/vinylogous Dieckmann cyclization cascade to assemble the bicyclo­[3.3.0]­octane subunit; and (3) a photo-Nazarov cyclization/intramolecular cycloetherification cascade to forge the 7-oxabicyclo­[4.2.1]­nonane core structure of the natural product.

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A concise and divergent approach for the total syntheses of four cembrane diterpenoids, namely (+)‐sarcophytin, (+)‐chatancin, (−)‐3‐oxochatancin, and (−)‐pavidolide B, has been developed, and it also led to the structural revision of (−)‐isosarcophytin. The key steps of the strategy feature a double Mukaiyama Michael addition/elimination, a Helquist annulation, two substrate‐controlled facial‐selective hydrations, and a pinacol rearrangement. The described syntheses not only achieved these natural products in an efficient manner, but also provided insight into the biosynthetic relationship between the two different skeletons.

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Commercially available neural networks software was applied for prediction of processing parameters with reference to the product quality of the dehydrated cooked rice. These results were verified with experimental data. The experimental results indicate good concurrence with the predicted data. A small capacity vibrofluidized bed drier was used to conduct the experimental studies. The inlet air temperature of 160C to 180C, the inlet air velocity of 3 to 6 ms -' and the resident time of 5 to 8 min were used in the study. The optimized process parameters were identified. The operation of the neural network model is discussed. The trained model can be applied in a nonlinear model predictive scheme to control the product moisture content.