Confusion regarding the usage of const,pointer and type alias [duplicate]

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• typedef pointer const weirdness 5 answers
• const, pointers, typedefs and stars [duplicate] 2 answers

Consider the following code,

const char *pstring;//pstring is a pointer to char
char *const pstring1;//pstring1 is a const pointer to char

Now consider the following example of type alias,

typedef char *pstring;//pstring is synonym for pointer to char
const pstring cstr = 0;

If we interpret pstring in the second statement as char*,then

how is cstr a const pointer to char and not a pointer to const char?