WordNet sense 1 (cautiously attentive):

careful

WordNet sense 2 (bearing in mind; attentive to):

aware, mindful

WordNet sense 3 (taking heed; giving close and thoughtful attention):

thoughtful, paying attention

WordNet sense 4 (giving attention):

advertent

WordNet sense 5 ((often followed by `to') giving care or attention):

attentive