、。
In the center stood a desk, and a red leather-upholstered swivel chair was placed beside it.
Literal
Center [in-には] desk [subject-が] was-set-up-and, red leather-upholstered swivel-chair [subject-が] was-placed-next.
Scene-setting prose. Two resultative-passive constructions mark the arrangement of furniture: 据えられていて ('had been set up and,' the ~ている form of the passive of 据える) and そえてあった ('had been placed beside,' the ~てある form of そえる 'to add, place alongside'). The distinction is subtle and revealing: ~ている + passive emphasizes the resulting state as observed, while ~てある ('has been X-ed [by someone, purposefully]') emphasizes the intentional placement — someone put it there with a purpose. Together they paint the room as deliberately arranged, each piece with an implied agent. 中央には ('in the center [topic]') uses には to make the location the topical frame.