Imperial Bancorp agreed to buy an Arizona bank.

The Los Angeles parent of Imperial Bank said it had reached agreement to acquire all of the outstanding shares of National Bank of Arizona, headquartered in Scottsdale. The merger, if approved by shareholders and regulators, will be completed Oct. 1, when interstate banking legislation takes effect in Arizona. Terms of the agreement were not disclosed. Imperial Bancorp has assets of $1.6 billion and 12 banking offices in California. National Bank of Arizona has assets of about $25 million.