For example Synesthetic vitamin K is soluble in water, but it is not soluble in fat. While natural Vitamin K is soluble in fat, but is not soluble water.
The basic molecule is the same. The form in which it is sold can be different eg. an ether or ester and there are differences between vitamin K1, K2 and K3.
As the chemical structure is same so both have similar properties regardless of origin. However the following article will help u in knowing the differences between two.
As far as the chemical and physical structure is same both have same effects, but why to go for synthetic when natural form is available. My first choice will always be natural.
Natural vitamins are better than synthetic forms because :
Many synthetic vitamins lack the transporters and co-factors associated with naturally occurring vitamins because they have been “isolated.” The Organic Consumers Association emphasizes that isolated vitamins cannot be used or recognized by the body in the same way as the natural version.
Synthetic vitamins are also devoid of necessary trace minerals and must use the body’s own mineral reserves which may lead to dangerous mineral deficiencies.