During the 20th century, jazz and classical music were blended into some exceptional creations. Several of those will be on display from the St. Louis Symphony and conductor Leonard Slatkin on Jan. 21. The program opens with Paul Turok’s tribute to a pioneer of jazz/classical crossover, A Joplin Overture. Then jazz piano master Aaron Diehl brings his Trio for their SLSO debut to play in Mary Lou Williams’ fascinating Zodiac Suite. Also on tap are John Alden Carpenter’s Krazy Kat and the beloved Gershwin work Rhapsody in Blue, featuring pianist Jeffrey Siegel.