Quidsi Inc., the Amazon.com Inc.-owned e-commerce unit that operates such sites as Diapers.com and Soap.com, has new leadership. Amazon veteran Maria Renz has taken over for co-founders Marc Lore and Vinit Bharara, a Quidsi spokeswoman says.

Amazon closed its $500 million acquisition of  Quidsi in 2011. Lore, the CEO, and Bharara, the chief operating officer, met in grade school, according to a company history posted by Quidsi. They opened their New Jersey office in 2006 and hired their first full-time employee in 2007. In April, Quidsi launched its tenth online store, Look.com, which sells children’s clothes and shoes.

The two “have decided to step down from their leadership positions at Quidsi to focus on new endeavors,” the spokeswoman says. No immediate comment was available from Lore or Bharara.

Quidsi says it operates independently from Amazon, No. 1 in the Internet Retailer Top 500 Guide.

Renz, the new Quidsi CEO, began working for Amazon in 1999, according to her LinkedIn profile.  She moves to Quidsi from her previous job as vice president, physical media and Canada, a position she started in January 2012.

Before that, she was vice president Amazon.com shoes, jewelry and watches, and CEO of Endless.com and MyHabit.com. In 2012, Amazon pulled the plug on Endless.com, a shoe and handbag retail site, and made it part of Amazon.com/fashion.  MyHabit.com, the flash-sale site launched in 2011 by Amazon.com Inc., won inclusion in Internet Retailer’s Hot 100 2012, a list of innovative e-retail sites and features.