ST_IntersectsRect function [Spatial]

ST_IntersectsRect(location,min,max)

Name	Type	Description
location	ST_Geometry	The point to be tested.
min	ST_Geometry	The minimum point value used to define the box.
max	ST_Geometry	The maximum point value used to define the box.

Select ST_IntersectsRect(ST_Point(1,1,4326),ST_Point(0,0,4326), ST_Point(3,3,4326))

Returns 1.