A number of sedative alkaloids were isolated from Sanjoin (酸棗仁), the seeds of Ziziphus vulgaris Lamark var. Spinosus Bunge (Rhamnaceae) Which is one of important Chinese herbal remedies used to treat insomnia and also sleepiness. These compounds were designated as Sanjoinine A, B, C, etc. depending on their order of increasing polarity on TLC. Sanjoinine-A, C_{31}H_{35}N₄O₄, mp. 249℃, [α]_{D} -316, Sanjoinene-B, C_{30}H_{42}N₄O₄, mp. 212-4℃, Sanjoinene, C_{29}H_{35}N₄O₄, mp 281-2℃, [α]_{D} - 272, Sanjoinine-D, C_{32}H_{46}N₄O_{5}, mp, 256-8℃, [α]_{D} - 53.6, Sanjoninine-F, C_{31}H_{42}N₄O_{5}, mp. 228-9℃, [α]_{D} - 215 and Sanjoinine-G₁, C_{31}H_{44}N₄O_{5}, mp. 236-8℃, [α]_{D} -68.6 were found as 14-membered cyclopeptide alkaloids.Sanjoinine-G₂, C_{30}H_{42}N₄O_{5}, mp 182℃, [α]_{D}-79.2 as open chain peptide alkaloid and Sanjoinine-E, C_{l9}H_{2l} NO₂, mp 166℃, [α]_{D}-146.2 and other six Sanjoinines as known aporphine alkaloids. The cyclopeptide alkaloids were subjected to heat treatment referring to the folkloric way of heat treatment of Sanjoin before use to obtain heatinduced artefact products. Sanjoinine-Ah, obtained by heat treatment on Sanjoin-A, one of major sedative components in sanjoin enhanced sedative activity and its structure was established as side-chain epimer of Sanjoinine-A. Present paper describes the isolation and structure determination of the sedative cyclopetide alkaloids and its heatinduced epimeric artefact.