The JSON sample you provided is not valid. Check it online with this JSON Validator http://jsonlint.com/. You need to remove the extra comma on line 59.
One you have valid json you can use this code to convert it to an array.
json_decode($json, true);
Array
(
[bpath] => http://www.sampledomain.com/
[clist] => Array
(
[0] => Array
(
[cid] => 11
[display_type] => grid
[ctitle] => abc
[acount] => 71
[alist] => Array
(
[0] => Array
(
[aid] => 6865
[adate] => 2 Hours ago
[atitle] => test
[adesc] => test desc
[aimg] =>
[aurl] => ?nid=6865
[weburl] => news.php?nid=6865
[cmtcount] => 0
)
[1] => Array
(
[aid] => 6857
[adate] => 20 Hours ago
[atitle] => test1
[adesc] => test desc1
[aimg] =>
[aurl] => ?nid=6857
[weburl] => news.php?nid=6857
[cmtcount] => 0
)
)
)
[1] => Array
(
[cid] => 1
[display_type] => grid
[ctitle] => test1
[acount] => 2354
[alist] => Array
(
[0] => Array
(
[aid] => 6851
[adate] => 1 Days ago
[atitle] => test123
[adesc] => test123 desc
[aimg] =>
[aurl] => ?nid=6851
[weburl] => news.php?nid=6851
[cmtcount] => 7
)
[1] => Array
(
[aid] => 6847
[adate] => 2 Days ago
[atitle] => test12345
[adesc] => test12345 desc
[aimg] =>
[aurl] => ?nid=6847
[weburl] => news.php?nid=6847
[cmtcount] => 7
)
)
)
)
)