11161
According to the regioselectivity and stereoselectivity , the AKRs studied can be divided in two groups : one of them showed preference for the reduction of the proximal keto group , resulting in the S - enantiomer of the corresponding alpha - hydroxy ketones .
 keto, alpha - hydroxy ketones
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 keto, alpha - hydroxy ketones