Can I write off stock losses from individual brokerage account against distribution from a simple ira?

The capital loss from your stock sale will first be offset by any capital gain. Any unused loss is then deducted from regular income which includes your IRA distribution to a maximum amount of $3,000.  Any loss left is carried over to subsequent years. 

Q. Can I write off stock losses from individual brokerage account against distribution from a simple IRA?

A.  No, at least, not directly. 

Capital losses, up to $3000, can be deducted against other ordinary income, including taxable retirement account distributions, including IRAs.