nginx alias phpmyadmin 失败，提示404

localhost 目录 c:/localhost
phpmyadmin 目录 c:/phpmyadmin
希望通过访问 http://localhost/phpmyadmin 访问 c:/phpmyadmin
配置nginx

server {
    listen 80;
    server_name localhost;
    root c:/phpmyadmin;
    index index.html index.htm index.php;

    location /phpmyadmin/ {
        root c:/phpmyadmin/;
    }

    location ~ \.php$ {
        try_files $uri =404;
        fastcgi_pass   127.0.0.1:9000;
        fastcgi_index  index.php;
        fastcgi_param  SCRIPT_FILENAME  $document_root$fastcgi_script_name;
        include        fastcgi_params;    
    }

}

运行提示404,localhost运行正常。