Abstract: The present invention provides zeolites and zeolite-like material having an enhanced microporosity. It was found that such zeolites can be obtained using a zeolite synthesis method comprising the preparation of a gel or solution for the synthesis of a zeolite, said gel or solution comprising appropriate amounts of (i) a conventional monomeric or polymeric silica source and (ii) a molecular template as a microstructuring agent, characterized in that said gel or solution further comprises an organosilane compound having limited self-assembling capacity.