Developer Alex S. Palmer is putting his namesake 18-story midtown office building on the market in advance of a loan for the tower coming due next year. Building owner Palmer Plaza Partners II still owes nearly $30 million on the loan, The Tennessean reports, and needs to sell the building at West End and 18th avenues or refinance. Lend Lease, Bethel University and Marsh are among the tenants in Palmer Plaza, which is 94 percent occupied. The building features a rooftop fitness center and 700-space…