Synergy K 120ct by Pure EncapsulationsWhat Is It? Vitamin K includes a group of compounds that contain a central ring structure with varying side chains. These differing side chains account for differences in absorption, bioavailability, transport and tissue distribution. Vitamin K1, phylloquinone, is the most common form and is found in plants and green vegetables. The vitamin K2 family, menaquinones, are less common and are found in meats, eggs, some cheeses, and fermented food, such as