<?php
$cachen = "2";
$site_name = "Иван-чай";
$slogan = "полезные свойства, противопоказания";
$adm_name = "admin";
echo json_encode([
'cachen' => $cachen,
'site_name' => $site_name,
'slogan' => $slogan,
'adm_name' => $adm_name
//Ещё куча параметров...
]);<?php
...
$data = curl_exec($ch);
$data = json_decode($data, true);
extract($data);
echo $site_name;
...require ('data/site_blok.php');
echo $site_name;