3. Amide Amide part has 3 bonds: two bonds are hornshaped working as male(+)and the other works as female(-). Note this difference when assembling. Nitrogen amide is originally prepared for Nitrogen of an amide group. Carbon amide, same shape as above but colored in black, is useful as a part at the location C4, C8 etc. as shown in Fig-5. Be sure to place the smaller angel 114°for the interior angel of pentagon of purine ring and larger angel 123°for the one hexagon. ORG-21 Double Bond Lock should be inserted between C=n of peptide group to restrict rotation. (Fig-6)