Almost every vitamin supplement sold in the grocery store or pharmacy in the USA is made from synthetic vitamins. Even the vitamin selection in most health food stores in the USA offers predominantly synthetic vitamins. After the chemist in the laboratory is done making synthetic vitamins, they look similar to real food derived vitamins under the microscope, but do not behave like food derived vitamins in the body. In fact, they can sometimes be harmful. Another thing that has shown to be a problem with isolated synthetic vitamins is that vitamins obtained from food have cofactors occurring in the food that work synergistically with the vitamins. For example, an orange has both vitamin C and a wide array of bioflavonoids which work with the vitamin C, while pure ascorbic acid does not have any bioflavonoids. Our bodies need both the food derived vitamins and the cofactors.
The B complex family of vitamins are extremely important for health. Most synthetic B vitamins are derived from coal tar. Coal tar is a known carcinogen and contains approximately 10,000 chemicals, of which only about 50% have been identified. 
Why would pharmaceutical companies push synthetic vitamins? My belief is that they do so because synthetics are much cheaper to produce than food extracted vitamins. So there is much more money to be made selling synthetic vitamins than food extracted vitamins.
If you take vitamin supplements, it is essential to make sure they are from a food source. Just because a supplement has the word natural does not mean it is derived from a food source. You must read the label to see if they disclose the source.
People often ask me what multivitamin I take and recommend to others. I use Liquid Vitamin Mineral Rush from SUNWARRIOR and highly recommend it. The ingredients are obtained from organically grown and wildcrafted raw plant sources and it does not contain any synthetics. Nor does it contain gluten or any other common allergens, chemicals, or fillers. The food derived ingredients come with a wide array of phytonutrients (cofactors) and a plant-based mineral complex with 72 minerals for increased absorbability; I believe that’s why they call it Rush!
Vitamin Mineral Rush contains a powerful array of food derived B complex vitamins with the methylcobalamin form of B12. This is the preferred form of B12. I suggest that you not waste your time with the cyancobalamin form of B12 because it is inferior. The other B vitamins in Rush are derived from organic guava, holy basil, and lemon extracts.
Most of the Vitamin C sold today is ascorbic acid made from fermented, nonorganic corn. Vitamin Mineral Rush gets its vitamin C from organic amla fruit. Amla fruit is an excellent source of both vitamin C and bioflavonoids.
The vitamin D in Vitamin Mineral Rush comes from lichen. This hardy plant exists in some of the most extreme areas on the planet such as arctic tundra, desserts, and rocky coast lines. And to my delight, lichen contain the better and more useable form of the vitamin, D3.
The vitamin E in Vitamin Mineral Rush comes from organic annatto. This is a great natural source of vitamin E. Beware of synthetic dl-alpha tocopherol, dl-alpha tocopherol acetate, or succinate. Vitamin E consists of 8 parts: alpha, beta, gama, and delta tocopherol and alpha, beta, gama, and delta tocotrienol. Annatto is a rich source of tocotrienols, the more beneficial part of vitamin E.
Finally a liquid multi vitamin and mineral complex that is made from organic, raw food! To my knowledge all the other liquid multi-vitamins contain coal tar and other synthetically produced vitamins. Liquid Vitamin Mineral Rush is something we can all greatly benefit from!