Abstract: This invention relates to new process for preparing certain optically active purine substituted cyclopentene derivatives and novel intermediates used in this process. In particular, the invention concerns the synthesis of the 1R-cis isomer of carbovir, (1R-cis)-amino-1,9-dihydro-9-[4-(hydroxymethyl)-2-cyclopenten-1-yl]-6H-pur in-6-one, an antiviral agent, and certain intermediates.

Abstract: A data processing device for providing data related to the categories of services available at locations along a highway in response to operator input is disclosed. The device includes a memory, a keyboard for entering input data identifying a desired service and an origin position into the memory. The input data is compressed before it is stored in the memory. The memory stores predetermined data in a compressed form related to the categories of services available at locations along the highway. The device also includes a microprocessor for retrieving from the memory the predetermined data which is a function of the input data. The microprocessor expands the retrieved compressed data into an operator readable form and provides the expanded data to a display for displaying the expanded retrieved data such as restaurants, gas stations, motels, or other services along the highway.