Sidney D. Jackman, Colonel, 14th Regiment Missouri Infantry, elected about September 1, 1862, resigned prior to November 25, 1862, subsequently raising Jackman's Regiment Missouri Cavalry, later appointed commanding officer of a Brigade of Recruits raised in Missouri and Arkansas, appointed Brig. General May 16, 1865, paroled September 25, 1865 having returned from Mexico

16th Missouri Infantry, also called 4, 7, 14, 15
Sidney D. Jackman, Colonel

M322: Compiled Service Records of Confederate Soldiers Who Served in Organizations from the State of Missouri

16th Missouri Infantry CSA

Commanded by Col. Sidney Drake Jackman, Col. Josiah H. Caldwell, Col. Levin M. Lewis, Lt. Col. Pleasant W. H. Cumming and Lt. Col. Jesse P. Herrell. Organized August 31, 1862 as the 7th Missouri Infantry, redesignated as the 16th Missouri Infantry on April 1, 1863. (Not to be confused with Col. Cyrus Franklin's 7th Missouri Infantry.) The 16th Missouri Infantry fought at the following engagements: Battle of Helena, Red River Campaign, Battle of Pleasant Hill, and Jenkins' Ferry. It surrendered on May 26, 1865 under Gen. E. Kirby Smith's Department of Trans-Mississippi.
http://www.missouridivision-scv.org/mounits/16mo-infantry.htm