Oracle 11g Release 2

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create table config1(acct_nbr, tablename) as (
  select 'regexp_replace(a.name,''/*/'')', 'abc' from dual );
1 rows affected

create table stu(name) as (
  select 'as' from dual union all select 'bb' from dual union all select 'cc' from dual);
3 rows affected

    declare
      vquery varchar2(32767);
      cursor c1 is select * from config1;
    begin
      for i in c1 loop
        vquery :='INSERT INTO all_acc_num(code,nbr_value) 
                  select '''||replace(i.acct_nbr, '''', '''''')||''', '||i.acct_nbr||' from ot.stu a';
        dbms_output.put_line(vquery);
        -- execute immediate vquery;
      end loop;
    end;
/
1 rows affected

dbms_output:
INSERT INTO all_acc_num(code,nbr_value) 
                  select 'regexp_replace(a.name,''/*/'')', regexp_replace(a.name,'/*/') from ot.stu a