[Biopython] Problem to retreive compound names using CID from PubChem

[sai nitin]

Hi all,

Myself sainitin i have list of CIDs from Pubchem Database  i want retereive
corresponding compundnames to automate this process im using Biopython
Entrez module (Entrez.esummary) when i give one CID and try to retreive name
of the compound  error is occuring

Code
h = Entrez.esummary(db = "pccompound",id = "449489")
r = Entrez.read(h)
r[0]["SourceName"]

Error
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
KeyError: 'SourceName'

Can anybody help me to solve this

Thanks
-- 

Sainitin D