Germany defender Shkodran Mustafi and Spanish striker Lucas Perez will have medicals at Arsenal on Friday.
The Gunners have reached a deal with Valencia for 24-year-old centre-back Mustafi, who is set to sign a five-year contract for a fee in excess of £35m.
They had already agreed to meet a 20m euro (£17.1m) clause to sign Deportivo La Coruna forward Perez, 27, who scored 17 goals in 37 games last season.
The deals would take Arsenal's spending to almost £100m since last season.
They have already added midfielders Granit Xhaka and Kelechi Nwakali, defender Rob Holding and forward Takuma Asano to their squad.
Everton were closing in on Lucas before Arsenal declared their interest.
Gunners boss Arsene Wenger has said he is not reluctant to spend money in the transfer market after being criticised by fans.
Speaking on Friday, the Frenchman said the club was "working on deals" and he was "99% confident" they would be concluded before the transfer window closes at 23:00 BST on 31 August.
"It was a strange transfer market," said Wenger. "I expected it to be easier than ever but it has been more difficult than ever.
"It looks like it will be frenetic in the last three days. Everyone has sat on money but we know they will all splash out now."