Tony-winning director Kenny Leon and others were also on hand to celebrate.
Full casting for the Huntington Theatre Company production of the drama has been announced.
O'Hara will head to Williamstown while Pinkham takes the stage at Joe's Pub.
Neil Patrick Harris, Sutton Foster, Kelli O'Hara, Ramin Karimloo, and more traveled to the 86th floor to drink in the breathtaking view.
Tony nominees Brian J. Smith and Adriane Lenox also attended the performance.
The Grammy Award winner joined the Jazz at Lincoln Center All-Stars in the production for one night only.
The newly minted honorees gather for the yearly Tony press junket at the Paramount Hotel.
Adriane Lenox of Broadway's After Midnight also joins the developmental reading.
Liz Callaway, Christina Bianco, and Ann Harada are also scheduled to perform.
The latest Broadway by the Year concert will take place on March 31 at The Town Hall.