Mail send is failed in SQL server when sending mail using SMTP

The mail could not be sent to the recipients because of the mail server failure. (Sending Mail using Account 16 (2017-09-08T11:32:55). Exception Message: Cannot send mails to mail server. (Service not available, closing transmission channel. The server response was: Cannot connect to SMTP server 8.8.4.4 (8.8.4.4:25), connect error 10060).
)

1)

		EXECUTE msdb.dbo.sysmail_add_account_sp
@account_name = 'Asus01',
@description = 'Sent Mail using MSDB',
@email_address = '[EDIT: Removed user name]@gmail.com',
@display_name = 'Vinayak',
@username='[EDIT: Removed user name]@gmail.com',
@password='[EDIT: Removed password]',
@mailserver_name = 'google-public-dns-b.google.com'

select * from sysmail_account

17	Asus01	Sent Mail using MSDB	vinayak.paul2011@gmail.com	Vinayak	NULL	2017-09-08 12:31:30.853	sa

2)

EXECUTE msdb.dbo.sysmail_add_profile_sp
@profile_name = 'Asus01',
@description = 'Profile used to send mail'		

-- select * from sysmail_profile

13	Asus01	Profile used to send mail	2017-09-08 12:41:50.767	sa

EXECUTE msdb.dbo.sysmail_add_profileaccount_sp
@profile_name = 'Asus01',
@account_name = 'Asus01',
@sequence_number = 1


--select * from sysmail_profileaccount

13	17	1	2017-09-08 12:44:37.163	sa

EXECUTE msdb.dbo.sysmail_add_principalprofile_sp
@profile_name = 'Asus01',
@principal_name = 'public',
@is_default = 1 ;

exec msdb.dbo.sp_send_dbmail @profile_name = 'Asus01', @recipients = 'paulvinayak70@gmail.com', @subject = 'Mail Test', @body = 'Mail Sent Successfully', @body_format = 'text'

select * from sysmail_allitems
		select * from 

unsent

sent_status column

failed