IUPAC Name: (5-Methyl-2-oxo-1,3-dioxol-4-yl)methyl(2S,5R,6R)-6-[[(2R)-2-amino-2-phenylacetyl]amino]-3,
3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylate
Molecular Formula: C₂₁H₂₃N₃O₇S 
Freely Rotating Bonds: 8
Polar Surface Area: 130.99 Å²
Index of Refraction: 1.653
Molar Refractivity: 114.31 cm³
Molar Volume: 311.9 cm³
Polarizability: 45.31 ×10^-24cm³
Surface Tension: 70.1 dyne/cm 
Density: 1.47 g/cm³
The Cas Register Number of Lenampicillin  is 86273-18-9 .The chemical synonyms of Lenampicillin (CAS No. 86273-18-9) are Lenampicillin ; Lenampicillin hydrochloride ; 1,3-Dioxole, 4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid deriv. ; 4-Thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid, 6-[(aminophenylacetyl)amino]-3,3-dimethyl-7-oxo-, (5-methyl-2-oxo-1,3-dioxol-4-yl)methyl ester, [2s-[2a,5a,6b(s*)]]- ; 4-Thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid, 6-[[(2r)-aminophenylacetyl]amino]-3,3-dimethyl-7-oxo-, (5-methyl-2-oxo-1,3-dioxol-4-yl)methyl ester, (2s,5r,6r)- (9ci) ; Antibiotic kbt 1585 ; Lenanpicillin ; Varacllin .The molecular structure of Lenampicillin (CAS No. 86273-18-9) is.

It is widely used as Acute bronchitis, pneumonia, pulmonary suppuration syndrome, pharyngitis, trauma and surgical wound such as a table of secondary infection, periodontal tissue inflammation, otitis media and so on.

To 6-APA as raw material, to maintain amino methyl acetoacetate, l0g 6-APA suspended in 100ml dichloromethane and l0ml methanol, at room temperature by adding 9ml triethylamine and 6.5g methyl acetoacetate, and then stirred at room temperature 2h. Decompression was concentrated, residue of compound (I), used directly for next step reaction.
The compound (I) dissolved in 70ml ethyl acetate and 18ml N, N-dimethyl formamide, at 50 ℃ by adding 1.7g of potassium bicarbonate, 1.2g of sodium iodide, and 8.2g 4 - chloro-methyl-5-A-1,3-dioxo-cyclopentene-2- one, at room temperature, stirring 15h. Add 40ml cold water, intense mixing 10min. Separation of the organic layer with 5% sodium chloride solution (2 × 40m1) Wash, dry and anhydrous magnesium sulfate. Drying off the organic layer containing compound (Ⅱ), without purification, used directly for next step reaction.
The above obtained compound (Ⅱ) solution cooling to 0 ~ 5 ℃, the stirring by adding 8.7g p-toluenesulfonic acid hydrate in 25ml ethyl acetate in a single solution. Within a few minutes that the precipitates crystalline precipitation, the suspension of 5 ~ 1012 to continue stirring 30min e, filter to collect precipitation precipitation, washing with ethyl acetate, may 20.4g compounds (Ⅲ), melting point 157 ~ 160 ℃ (decomposition ). Three-step total yield of 88%.
10g compounds (Ⅲ) suspended in 100ml dichloromethane solution, in 0 ~ 5 ℃ and stirring, add 2.8ml triethylamine and 4g ammonium bicarbonate. In a phased manner over 15min by adding 5g of benzene Gly-chloride, and then in the 7 ~ 10 ℃ under stirring 50min. Add 70ml water, under the 0 ~ 5 ℃ with 3mol / L sodium hydroxide solution transferred Ph7.4. After filtration, separation of methylene chloride layer washed with 5% sodium chloride solution. In the 0 ~ 5 ℃ and stirring, to the dichloromethane solution by adding 80ml saturated saline, then add 2mol / L hydrochloric acid to the Ph value of 1.5. Separation of the organic layer, washed with saturated brine, anhydrous magnesium sulfate drying. Decompression was concentrated, residue crystals with 40ml 2-butanone .
Coarse crystals soluble in dichloromethane, vacuum concentration was a residue, add 20ml isopropyl alcohol and 40ml ethyl acetate, in place overnight under 5 ℃. Obtained colorless crystals filtered, washed with cold ethyl acetate, may 7.6g lenampicillin hydrochloride, yield 76%, melting point 145 ℃ (decomposition).
Method 2: ampicillin as raw material. Ampicillin and dehydration condensation of benzaldehyde to form a Schiff's base while ampicillin on the protection of free amino, and then, and 4 - halogen-methyl -5 - methyl-1,3 - dioxa -4 - cyclopentene -2 - one (halogen = bromine or chlorine) reaction, the introduction of two on the chain, and finally methanol solution of hydrogen chloride acid decomposition Schiff's base, off to protect the base and get lenampicillin the hydrochloride.

Moderately toxic by intravenous and subcutaneous routes. Mildly toxic by ingestion. An experimental teratogen. Experimental reproductive effects. When heated to decomposition it emits toxic fumes of SO_x, NO_x, and HCl. See also ESTERS.
Hazard Codes: Xi  
Risk Statements: 36/37/38
R36/37/38: Irritating to eyes, respiratory system and skin.
Safety Statements: 26-36
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. 
S36: Wear suitable protective clothing.