The Western Kunlun Range in northwestern Tibet records a history of enlargement of the Central Asian crust. In the Early Ordovician a south-dipping intra-oceanic subduction-accretion complex was accreted to the Tarim block, forming an Andean-type margin in the Late Ordovician. This margin grew southward (present-day coordinates) in the Early Silurian, with an accretionary complex on its southern side against which the Kudi gneiss-schist complex was attached. Clastic sediments continued to infill forearc/intra-arc basins on the top of the arc-accretionary complexes during Devonian-Carboniferous time. In the Early to Mid-Carboniferous, tectonic and magmatic quiescence is indicated by an absence of volcanic and plutonic rocks in the Kudi area, whereas subduction was still active in the western part of the range in the Gaz area near the present-day Pamir syntaxis. A Late Carboniferous-Permian to Early Mesozoic accretionary arc and forearc developed in front of the Andean-type margin, indicating that north-dipping subduction was renewed in the Late Carboniferous. Final collision of the Karakoram-North Qiangtang block to the western Kunlun orogenic collage by the Mid-Jurassic resulted in closure of Paleo-Tethys. The accretion and development of the Western Kunlun orogen contributed huge quantities of material for the crustal growth of Asia.

An efficient stereoselective total synthesis of the furo[2,3-c]pyridine thiopyrimidine HIV-1 reverse transcriptase inhibitors, PNU-142721 and PNU-109886, has been developed. A convergent approach was utilized, providing direct access to the desired (S)-configuration of the molecule by making use of the alkylation of 4-amino-6-chloro-2-thiopyrimidine with the appropriate (R)-1-chloroethyl furo[2,3-c]pyridine intermediates. The successful preparation makes use of an efficient enzymatic kinetic resolution of the key 1-hydroxyethyl furo[2,3-c]pyridine intermediates to establish stereochemical control of the respective stereogenic centers. In addition, a workable asymmetric reduction strategy was developed for the synthesis of PNU-109886. Prudent reagent selection for the chlorination required for the final coupling reactions allowed for maintenance of the stereochemical integrity of the target compounds. Structural assignment of the absolute configuration of PNU-142721 and PNU-109886 as the (S)-enantiomer was confirmed by X-ray crystallographic analysis.

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A new family of benzene-based chiral heterodisulfoxide ligands L1-L5 was synthesized in a single step. These disulfoxide ligands were applied in the rhodium-catalyzed asym-