Google Inc's disappointing first-quarter results left Wall Street unfazed about the internet giant's ability to come to grips with a shift to the fast-growing mobile advertising market.

Google shares were down 2 percent in premarket trading on Thursday and at least 12 brokerages cut their target price on the stock.

But most analysts kept their "buy" rating on the stock.

"Despite an expectations-miss quarter, Google remains one of the best-positioned stocks for many of the secular growth drivers in the Internet space," RBC Capital analyst Mark Mahaney, who kept his "outperform" rating on the stock, said in a note to clients.

Of the 46 analysts covering Google, 35 have a "buy" or equivalent rating on the stock. Nobody has a "sell".

Google, Facebook Inc and Twitter Inc are revamping their products and advertising business to try to take advantage of a global shift to mobile phones and tablets.

Advertising rates on mobile phones are typically cheaper than traditional online ads because of their smaller screens. But mobile advertising continues to make up a bigger slice of the revenue of Internet companies.

Goldman Sachs, which has a "neutral" rating on Google's shares, said it expects the stock to remain range-bound in the near-term as the market waits for mobile cost-per-click rates to improve.

The company reported a 26 percent increase in paid clicks volumes but the average cost-per-click declined 9 percent.

"Google remains a core internet holding and we reiterate our "overweight" rating," Morgan Stanley said in a note titled, "Keep calm and search on".

Deutsche Bank analyst Ross Sandler cut his target price on Google by 6 percent to $625, but said he continued to view Google as a "top idea and a safe-haven" during times of high volatility in the consumer internet market.